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1.
Chinese Medical Journal ; (24): 2214-2222, 2021.
Artigo em Inglês | WPRIM | ID: wpr-887598

RESUMO

BACKGROUND@#Accumulating evidence suggests that lithium influences mesenchymal stem cell (MSC) proliferation and osteogenic differentiation. As decreased bone formation in femoral heads is induced by glucocorticoids (GCs), we hypothesized that lithium has a protective effect on GC-induced osteonecrosis of femoral heads (ONFH).@*METHODS@#A rat ONFH model was induced by methylprednisolone (MP) and the effect of lithium chloride on the models was evaluated. Micro-computed tomography (CT)-based angiography and bone scanning were performed to analyze the vessels and bone structure in the femoral heads. Hematoxylin and eosin and immunohistochemical staining were performed to evaluate the trabecular structure and osteocalcin (OCN) expression, respectively. Bone marrow-derived MSCs were isolated from the models, and their proliferative and osteogenic ability was evaluated. Western blotting and quantitative real-time polymerase chain reaction were performed to detect osteogenic-related proteins including Runx2, alkaline phosphatase, and Collagen I.@*RESULTS@#Micro-CT analysis showed a high degree of osteonecrotic changes in the rats that received only MP injection. Treatment with lithium reduced this significantly in rats that received lithium (MP + Li group); while 18/20 of the femoral heads in the MP showed severe osteonecrosis, only 5/20 in the MP + Li showed mild osteonecrotic changes. The MP + Li group also displayed a higher vessel volume than the MP group (0.2193 mm3vs. 0.0811 mm3, P < 0.05), shown by micro-CT-based angiography. Furthermore, histological analysis showed better trabecular structures and more OCN expression in the femoral heads of the MP + Li group compared with the MP group. The ex vivo investigation indicated higher proliferative and osteogenic ability and upregulated osteogenic-related proteins in MSCs extracted from rats in the MP + Li group than that in the MP group.@*CONCLUSIONS@#We concluded that lithium chloride has a significant protective effect on GC-induced ONFH in rats and that lithium also enhances MSC proliferation and osteogenic differentiation in rats after GC administration.


Assuntos
Animais , Ratos , Diferenciação Celular , Cabeça do Fêmur , Necrose da Cabeça do Fêmur/tratamento farmacológico , Glucocorticoides , Cloreto de Lítio , Células-Tronco Mesenquimais , Osteogênese , Ratos Sprague-Dawley , Microtomografia por Raio-X
2.
Braz. dent. j ; 31(6): 640-649, Nov.-Dec. 2020. tab, graf
Artigo em Inglês | LILACS, BBO | ID: biblio-1132358

RESUMO

Abstract The purpose of this investigation was to evaluate the effects of lithium chloride (LiCl) on the socket healing of estrogen-deficient rats. Seventy-two rats were allocated into one of the following groups: Control, Ovariectomy and LiCl (150 mg/kg/2 every other day orally) + Ovariectomy. Animals received LiCl or water from the 14th day post-ovariectomy, until the completion of the experiment. On the 21st day after ovariectomy, the first molars were extracted. Rats were euthanized on the 10th, 20th and 30th days following extractions. Bone healing (BH), TRAP positive cells and immunohistochemical staining for OPG, RANKL, BSP, OPN and OCN were evaluated. The Ovariectomy group presented decreased BH compared to the LiCl group at 10 days, and the lowest BH at 20 days (p<0.05). At 30 days, the Ovariectomy and LiCl-groups presented lower BH than that of the Control (p<0.05). The number of TRAP-stained cells was the lowest in the LiCl group at 20 days and the highest in the Ovariectomy group at 30 days (p<0.05). At 10 days of healing, the LiCl group demonstrated stronger staining for all bone markers when compared to the other groups, while the Ovariectomy group presented higher RANKL expression than that of the Control (p<0.05). LiCl enhanced bone healing in rats with estrogen deficiency, particularly in the initial healing phases. However, as data on the effects of lithium chloride on bone tissue are still preliminary, more studies related to its toxicity and protocol of administration are necessary before its application in clinical practice.


Resumo O objetivo deste estudo foi avaliar os efeitos do Cloreto de Lítio (ClLi) na cicatrização de alvéolos de ratas deficientes em estrogênio. Setenta e duas ratas foram alocadas em um dos seguintes grupos: Controle, Ovariectomia e Cloreto de Lítio (150mg/kg/ oralmente a cada 2 dias) + ovarectomia. Os animais receberam ClLi ou água a partir do 14º dia pós-ovariectomia, até a conclusão do experimento. No 21º dia após a ovariectomia, os primeiros molares foram extraídos. As ratas foram sacrificadas nos dias 10, 20 e 30 após extrações. Foram avaliadas a cicatrização óssea (BH), células positivas para TRAP e coloração imuno-histoquímica para OPG, RANKL, BSP, OPN e OCN. O grupo Ovariectomia apresentou BH diminuída em comparação ao grupo LiCl aos 10 dias e a menor BH aos 20 dias (p<0,05). Aos 30 dias, os grupos Ovariectomia e LiCl apresentaram menor BH do que o Controle (p<0,05). O número de células positivas para TRAP foi menor no grupo ClLi em 20 dias e o maior no grupo Ovariectomia em 30 dias (p<0,05). Aos 10 dias de cicatrização, o grupo ClLi demonstrou imunomarcação mais intensa em todos os marcadores testados quando comparado aos outros grupos, enquanto o grupo Ovariectomia apresentou maior expressão de RANKL do que a do controle (p<0,05). O ClLi melhorou a cicatrização óssea em ratos com deficiência de estrogênio, particularmente nas fases iniciais do reparo. No entanto, como os dados sobre os efeitos do cloreto de lítio no tecido ósseo ainda são preliminares, mais estudos relacionados à sua toxicidade e protocolo de administração são necessários antes de sua aplicação na prática clínica.


Assuntos
Humanos , Animais , Feminino , Ratos , Extração Dentária , Cloreto de Lítio , Cicatrização , Ovariectomia , Ratos Wistar , Alvéolo Dental , Estrogênios
3.
Rev. invest. clín ; 71(2): 116-123, Mar.-Apr. 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1289677

RESUMO

Abstract Background Adenosine A1 receptor (AA1R) is widely present in the central nervous system, exerting brain protective antiepileptic effects, mainly by binding corresponding G proteins. We evaluated the neuroprotective effects of AA1R on hippocampal neuronal injury after lithium chloride-pilocarpine-induced epilepsy in rats. Materials and Methods A total of 60 male SD rats were randomly divided into four groups (n = 15/group): normal control, epilepsy, epilepsy + AA1R antagonist (DPCPX), and epilepsy + AA1R agonist (2-CAdo). An epilepsy model was established through kindling by lithium chloride-pilocarpine. The four groups were observed on days 1, 14, and 30. Pathological and morphological changes of hippocampal neurons were observed by HE staining; apoptosis was detected by TUNEL assay. Caspase-3 and GABA receptor expressions were detected by Western blot. Results In the hippocampal CA3 area of the epilepsy group, the cellular structure was not neatly arranged, and some neurons were swelling, thick, and incomplete. Compared with the epilepsy group at the same time point, cells in the epilepsy + DPCPX group had an increased distortion, disorganization, edema, cytoplasmic vacuoles, and degeneration. In the epilepsy + 2-CAdo group, cell arrangement was regular and orderly, and structural damages were lessened. Compared with the normal control group at the same time point, the epilepsy group underwent evident neuronal apoptosis, with a significantly higher apoptotic index (AI) (p < 0.05). Compared with the epilepsy group, the neuronal apoptosis of the epilepsy + DPCPX group was boosted, and the AI significantly increased (p < 0.05). The neuronal apoptosis of the epilepsy + 2-CAdo group was inhibited, and the AI significantly decreased (p < 0.05). Compared with the epilepsy group, the caspase-3 expression levels of the epilepsy + DPCPX group on days 14 and 30 were significantly upregulated (p < 0.05), but those of the epilepsy + 2-CAdo group were significantly downregulated (p < 0.05). Conclusions AA1R abated cell edema and reduced apoptosis, exerting neuroprotective effects on hippocampal neuronal injury after lithium chloride-pilocarpine-induced epilepsy.


Assuntos
Animais , Masculino , Ratos , Fármacos Neuroprotetores/farmacologia , Epilepsia/tratamento farmacológico , Agonistas do Receptor A1 de Adenosina/farmacologia , Hipocampo/efeitos dos fármacos , Pilocarpina/toxicidade , Fatores de Tempo , Ratos Sprague-Dawley , Apoptose/efeitos dos fármacos , Cloreto de Lítio/toxicidade , Modelos Animais de Doenças , Hipocampo/patologia , Neurônios/patologia
4.
Anatomy & Cell Biology ; : 207-213, 2017.
Artigo em Inglês | WPRIM | ID: wpr-50231

RESUMO

Glycogen synthase kinase (GSK)-3β and related enzymes are associated with various forms of neuroinflammation, including spinal cord injury (SCI). Our aim was to evaluate whether lithium, a non-selective inhibitor of GSK-3β, ameliorated SCI progression, and also to analyze whether lithium affected the expression levels of two representative GSK-3β–associated molecules, nuclear factor erythroid 2-related factor-2 (Nrf-2) and heme oxygenase-1 (HO-1) (a target gene of Nrf-2). Intraperitoneal lithium chloride (80 mg/kg/day for 3 days) significantly improved locomotor function at 8 days post-injury (DPI); this was maintained until 14 DPI (P<0.05). Western blotting showed significantly increased phosphorylation of GSK-3β (Ser9), Nrf-2, and the Nrf-2 target HO-1 in the spinal cords of lithium-treated animals. Fewer neuropathological changes (e.g., hemorrhage, inflammatory cell infiltration, and tissue loss) were observed in the spinal cords of the lithium-treated group compared with the vehicle-treated group. Microglial activation (evaluated by measuring the immunoreactivity of ionized calcium-binding protein-1) was also significantly reduced in the lithium-treated group. These findings suggest that GSK-3β becomes activated after SCI, and that a non-specific enzyme inhibitor, lithium, ameliorates rat SCI by increasing phosphorylation of GSK-3β and the associated molecules Nrf-2 and HO-1.


Assuntos
Animais , Ratos , Western Blotting , Quinases da Glicogênio Sintase , Glicogênio Sintase , Glicogênio , Heme Oxigenase-1 , Heme , Hemorragia , Cloreto de Lítio , Lítio , Fosforilação , Traumatismos da Medula Espinal , Medula Espinal
5.
Journal of Southern Medical University ; (12): 201-205, 2014.
Artigo em Chinês | WPRIM | ID: wpr-356955

RESUMO

<p><b>OBJECTIVE</b>To investigate the changes in the functional activity of glycogen synthase kinase-3 (GSK-3) in the hepatic tissue after endotoxin (lipopolysaccharide, LPS) tolerance and explore the effects of LPS-induced GSK-3 inhibition on glycogen metabolism in the liver.</p><p><b>METHODS</b>Male SD rats were randomly divided into normal control, endotoxin pretreatment and GSK-3 inhibitor (lithium chloride) groups with corresponding pretreatments prior to a large dose of LPS challenge (10 mg/kg) to induce liver injury. Glycogen deposition and content in the hepatic tissue was detected using periodic acid-Schiff (PAS) staining and a glycogen quantification kit, respectively. Western blotting was performed for semi-quantitative analysis of protein level and inhibitory phosphorylation of GSK-3, and a Coomassie brilliant blue G-250-based colorimetric assay was used to detect calpain activity in the liver.</p><p><b>RESULTS</b>Glycogen content in the liver decreased significantly after LPS challenge in all the 3 groups (P<0.05) but showed no significant difference among the groups (P>0.05). Both LPS and lithium chloride pretreatments caused a significant increase of liver glycogen content (P<0.05). LPS pretreatment induced inhibitory phosphorylation of GSK-3β (P<0.05) and partial cleavage of GSK-3α but did not affect the expression of GSK-3 protein (P>0.05). Large-dose LPS challenge significantly increased the activity of calpain in the liver tissue (P<0.05) to a comparable level in the 3 groups (P>0.05).</p><p><b>CONCLUSION</b>Endotoxin pretreatment induces inhibitory phosphorylation of GSK-3β and partial cleavage of GSK-3α and promotes the deposition of liver glycogen but does not affect the activity of calpain, which may contribute to an increased glycogen reserve for energy supply in the event of large-dose LPS challenge.</p>


Assuntos
Animais , Masculino , Ratos , Calpaína , Metabolismo , Glicogênio , Metabolismo , Quinase 3 da Glicogênio Sintase , Metabolismo , Lipopolissacarídeos , Cloreto de Lítio , Farmacologia , Fígado , Metabolismo , Patologia , Ratos Sprague-Dawley
6.
Pesqui. vet. bras ; 33(6): 719-723, June 2013. tab
Artigo em Português | LILACS | ID: lil-680785

RESUMO

A aversão alimentar condicionada é uma técnica que pode ser utilizada em animais para evitar a ingestão de plantas tóxicas. O presente estudo teve como objetivo testar a eficiência e durabilidade da aversão alimentar condicionada em caprinos para evitar o consumo de Ipomoea carnea subsp. fistulosa. Foram utilizados 14 caprinos jovens da raça Moxotó, que foram adaptados ao consumo da planta. Inicialmente foi administrada I. carnea subsp. fistulosa dessecada e triturada misturada à ração concentrada por 30 dias e, posteriormente, foi fornecida a planta verde por mais 10 dias. Para constatação da adaptação ao consumo da planta os caprinos foram colocados a pastar em um piquete de 510 m² onde tinha sido plantada I. carnea subsp. fistulosa em uma área de 30m² (10 plantas/m²). No 42º dia de experimento, após a constatação do consumo espontâneo os animais receberam a planta verde individualmente na baia por alguns minutos, e todos os animais que consumiam qualquer quantidade da planta foram tratados com uma solução de LiCl na dose 175mg por kg de peso vivo. Este procedimento repetiu-se por mais dois dias. Posteriormente, os caprinos foram divididos em dois grupos: Grupo 1 com seis animais, quatro deles avertidos e dois não avertidos (facilitadores); e o Grupo 2, com oito caprinos, todos avertidos. Para constatar a eficiência e duração da aversão e a influência de animais facilitadores na durabilidade da aversão, os caprinos foram colocados a pastar, em dias alternados, três dias por semana, durante duas horas, no piquete plantado com I. carnea subsp. fistulosa. Por 12 meses os animais foram monitorados durante o pastejo, identificando-se o consumo e a preferência dos animais pelas plantas presentes no piquete. No Grupo 1 tanto os caprinos avertidos quanto os não avertidos iniciaram a ingerir a planta em 1-6 semanas e gradualmente foram aumentando a planta consumida, mas nunca a ingeriram exclusivamente. Nenhum caprino do Grupo 2 iniciou a ingestão da planta durante os 12 meses de experimento. Após esse período a área do piquete destinada ao plantio de I. carnea subsp. fistulosa foi ampliada para 80m² e os animais foram novamente introduzidos, com tempo de pastejo na área aumentado para quatro horas durante cinco dias na semana. Nesta fase todos os caprinos do Grupo 1 ingeriram a planta em grande quantidade. Os caprinos do Grupo 2 iniciaram gradualmente a ingerir a planta e a aversão se extinguiu, em todos os animais, após dois meses. A concentração de swainsonina em I. carnea subsp. fistulosa foi de 0,052±0,05% (média±SD). Conclui-se que a aversão alimentar condicionada é eficiente para evitar a ingestão de I. carnea subsp. fistulosa. No entanto, a duração da mesma depende, entre outras coisas, da quantidade de planta presente na área de pastoreio e do tempo de exposição e se extingue rapidamente por facilitação social.


Conditioned food aversion is a technique that can be used to train livestock to avoid ingestion of poisonous plants. This study tested the efficacy and durability of conditioned food aversion to eliminate goat's consumption of Ipomoea carnea subsp. fistulosa. We used 14 young Moxotó goats, which were initially adapted to the consumption of the plant by offering dried I. carnea subsp. fistulosa with their concentrate diet for 30 days, and then subsequently providing green plant for another 10 days. To confirm the spontaneous consumption of the plant, the goats were allow to graze in a paddock of 510m² where I. carnea subsp. fistulosa had been planted in an area of 30m² (10 plants/m²). On day 42, 12 goats were offered fresh green plant individually in a pen for a few minutes, and after the consumption of any amount of the plant they were treated orally with a solution of LiCl at a dose 175mg per kg of body weight. This procedure was repeated for two more consecutive days. Thereafter, the goats were divided into two groups: Group 1 with four averted and two non-averted goats; and Group 2 with eight averted goats. To verify the efficacy and duration of aversion, both groups were introduced into the paddock with I. carnea subsp. fistulosa three days a week for two hours daily. In Group 1, with two non-averted and four averted goats, all animals started to ingest the plant after 1-6 weeks of grazing. They continually increased their consumption of the plant, but never consumed the plant exclusively. None of the goats of Group 2 goats started eating the plant during the 12 months of observation. After this period the area of the paddock planted with I. carnea subsp. fistulosa was expanded to 80 m² and grazing time was increased to four hours per day for five days a week. At this stage all the goats in Group 1 ingested the plant in large quantities. The goats from Group 2 gradually started to eat the plant and aversion was extinguished in all animals after two months. Swainsonine concentration of I. carnea subsp. fistulosa was 0.052±0.05% (mean ±SD). It was concluded that conditioned food aversion was effective in reducing goat consumption of I. carnea subsp. fistulosa, but the duration of aversion depends on the time of grazing and amount of plant available. However, the aversion was quickly extinguished by social facilitation when averted animals grazed with non-averted animals.


Assuntos
Animais , Convolvulaceae/toxicidade , Intoxicação/diagnóstico , Intoxicação/veterinária , Plantas Tóxicas/toxicidade , Cloreto de Lítio/toxicidade
7.
International Journal of Oral Science ; (4): 1-6, 2013.
Artigo em Inglês | WPRIM | ID: wpr-358198

RESUMO

This study aimed to compare epithelial cells derived from human embryonic stem cells (hESCs) to human ameloblast-lineage cells (ALCs), as a way to determine their potential use as a cell source for ameloblast regeneration. Induced by various concentrations of bone morphogenetic protein 4 (BMP4), retinoic acid (RA) and lithium chloride (LiCl) for 7 days, hESCs adopted cobble-stone epithelial phenotype (hESC-derived epithelial cells (ES-ECs)) and expressed cytokeratin 14. Compared with ALCs and oral epithelial cells (OE), ES-ECs expressed amelogenesis-associated genes similar to ALCs. ES-ECs were compared with human fetal skin epithelium, human fetal oral buccal mucosal epithelial cells and human ALCs for their expression pattern of cytokeratins as well. ALCs had relatively high expression levels of cytokeratin 76, which was also found to be upregulated in ES-ECs. Based on the present study, with the similarity of gene expression with ALCs, ES-ECs are a promising potential cell source for regeneration, which are not available in erupted human teeth for regeneration of enamel.


Assuntos
Humanos , Ameloblastos , Fisiologia , Amelogênese , Genética , Amelogenina , Proteína Morfogenética Óssea 4 , Farmacologia , Técnicas de Cultura de Células , Diferenciação Celular , Linhagem Celular , Linhagem da Célula , Células-Tronco Embrionárias , Fisiologia , Células Epiteliais , Fisiologia , Fator 8 de Crescimento de Fibroblasto , Proteínas Hedgehog , Proteínas de Homeodomínio , Queratinas , Classificação , Cloreto de Lítio , Farmacologia , Fator de Transcrição MSX1 , Mucosa Bucal , Biologia Celular , Fenótipo , Regeneração , Fisiologia , Pele , Biologia Celular , Fatores de Transcrição , Tretinoína , Farmacologia
8.
Journal of the Korean Society of Biological Psychiatry ; : 159-165, 2013.
Artigo em Coreano | WPRIM | ID: wpr-725002

RESUMO

OBJECTIVES: Mechanisms of clinical synergistic effects, induced by co-treatments of lithium and valproate, are unclear. Extracellular signal-regulated kinase (ERK) has been suggested to play important roles in mechanisms of the action of mood stabilizers. In this study, effects of co-treatments of lithium and valproate on the ERK1/2 signal pathway and its down-stream transcription factors, ELK1 and C-FOS, were investigated in vitro. METHODS: PC12 cells, human pheochromocytoma cells, were treated with lithium chloride (30 mM), valproate (1 mM) or lithium chloride + valproate. The phosphorylation of ERK1/2 was analyzed with immunoblot analysis. Transcriptional activities of ELK1 and C-FOS were analyzed with reporter gene assay. RESULTS: Single treatment of lithium and valproate increased the phosphorylation of ERK and transcriptional activities of ELK1 and C-FOS, respectively. Combined treatments of lithium and valproate induced more robust increase in the phosphorylation of ERK1/2 and transcriptional activities of ELK1 and C-FOS, compared to those in response to single treatment of lithium or valproate. CONCLUSIONS: Co-treatments of lithium and valproate induced synergistic increase in the phosphorylation of ERK1/2 and transcriptional activities of its down-stream transcription factors, ELK1 and C-FOS, compared to effects of single treatment. The findings might suggest potentiating effects of lithium and valproate augmentation treatment strategy.


Assuntos
Animais , Humanos , Genes Reporter , Cloreto de Lítio , Lítio , Células PC12 , Feocromocitoma , Fosforilação , Fosfotransferases , Transdução de Sinais , Fatores de Transcrição , Ácido Valproico
9.
Pesqui. vet. bras ; 32(8): 707-714, ago. 2012. ilus
Artigo em Português | LILACS | ID: lil-649508

RESUMO

A aversão alimentar condicionada é uma técnica que pode ser utilizada em animais para evitar a ingestão de plantas tóxicas. A técnica foi utilizada em uma fazenda para controlar a intoxicação por Turbina cordata e em outra para Ipomoea carnea subsp. fistulosa. Os caprinos eram presos à noite, e na manhã do dia seguinte lhes era ofertada a planta verde, recém-colhida, por dez minutos. Os caprinos que ingerissem qualquer quantidade da planta eram identificados, pesados e tratados com LiCl na dose de 175mg/kg peso vivo através de sonda esofágica. No rebanho da fazenda na que havia T. cordata a técnica foi aplicada a cada dois meses durante o período em que a planta é encontrada. Durante todo o experimento, de dezembro de 2009 a abril de 2011 não ocorreu nenhum novo caso de intoxicação no rebanho e diminuiu gradualmente o número de animais avertidos e a quantidade de planta que ingeriam os mesmos durante o processo de aversão. Na fazenda na que ocorria intoxicação por I. carnea a maioria de rebanho foi avertido em dezembro de 2010, 15-20 dias antes do início das chuvas, e os animais não ingeriram a planta espontaneamente no campo até setembro-outubro de 2011, durante o período da seca, quando havia extrema carência de forragem e iniciaram a ingerir a planta no campo. Posteriormente, apesar de três tratamentos aversivos com 21 dias de intervalo, os animais continuaram a ingerir a planta e ocorreram casos clínicos. A técnica de aversão alimentar condicionada demonstrou ser eficiente e viável para o controle da intoxicação por T. cordata. Para a intoxicação por I. carnea a técnica impediu a ingestão da planta somente durante a época de chuvas, mas não durante a seca, quando há pouca disponibilidade de forragem. A diferença nos resultados com as duas plantas é, aparentemente, resultante das condições epidemiológicas diferentes nas que ocorrem as intoxicações. T. cordata desaparece durante a maior parte do período de seca. A planta rebrota e fica verde durante o fim de seca, quando diminui a oferta de forragem, por curto espaço de tempo, permanecendo verde durante a época de chuvas. I. carnea, por crescer próximas as fontes de água, em áreas húmidas, permanece verde durante todo o período da seca, quando é maior a escassez de forragem, favorecendo desta forma a ingestão da planta pelos animais.


Conditioned food aversion is used to train livestock to avoid the ingestion of toxic plants. This technique was used to control Turbina cordata poisoning in goats in one farm, and to control Ipomoea carnea subsp. fistulosa poisoning in another farm. The goats were penned at night and the next morning the green plants were offered for 10 minutes. Goats that ingested any amount of the plant were treated through a gastric tube with 175mg of LiCl/kg body weight. In the flock in which the poisoning by T. cordata was occurring, the goats were averted every two months during the period that the plant was found in the pastures. During the experiment, from December 2009 to April 2011, new cases of poisoning were not observed, and there was a progressive decrease in the number of goats that ingested the plant and were averted. In the farm where I. carnea poisoning was occurring, most of the goats were averted in December 2010, 15-20 days before the first rains. The goats of this flock did not ingest the plant spontaneously in the field until September-October 2011, when, due to the dry season, there was a severe forage shortage, and the goats started to ingest the plant in the field. Later, despite three aversive treatments with 21 days intervals, the goats continued to ingest the plant and some animals became poisoned. In conclusion, conditioned food aversion was effective in to control intoxication by T. cordata. The technique was also effective in conditioning goats to avoid consuming I. carnea during the rainy season, but not during the dry season, with low forage availability in the field. The differences in these results seem to be due to the epidemiology of both poisonings: T. cordata is senescent and unavailable during most of the dry period, and green biomass is typically available either at the very end of the dry season, for a short period of time, and during the rainy season when there is no shortage of forage. In contrast, I. carnea grows in wet areas near water sources, and stays green during the dry period when there is a lack of other forage.


Assuntos
Animais , Cloreto de Lítio/administração & dosagem , Comportamento Alimentar , Comportamento Alimentar , Ipomoea/toxicidade , Ovinos/imunologia , Convolvulaceae/toxicidade , Intoxicação por Plantas/veterinária , Swainsonina/toxicidade
10.
Arq. bras. cardiol ; 98(3): 243-251, mar. 2012. tab
Artigo em Português | LILACS | ID: lil-622515

RESUMO

FUNDAMENTO: A Contração Pós-Repouso (CPR) do músculo cardíaco fornece informações indiretas sobre a manipulação de cálcio intracelular. OBJETIVO: Nosso objetivo foi estudar o comportamento da CPR e seus mecanismos subjacentes em camundongos com infarto do miocárdio. MÉTODOS: Seis semanas após a oclusão coronariana, a contratilidade dos Músculos Papilares (MP) obtidos a partir de camundongos submetidos à cirurgia sham (C, n = 17), com infarto moderado (MMI, n = 10) e grande infarto (LMI, n = 14), foi avaliada após intervalos de repouso de 10 a 60 segundos antes e depois da incubação com cloreto de lítio (Li+) em substituição ao cloreto de sódio ou rianodina (Ry). A expressão proteica de SR Ca(2+)-ATPase (SERCA2), trocador Na+/Ca2+ (NCX), fosfolambam (PLB) e fosfo-Ser (16)-PLB foi analisada por Western blotting. RESULTADOS: Os camundongos MMI apresentaram potenciação de CPR reduzida em comparação aos camundongos C. Em oposição à potenciação normal para camundongos C, foram observadas degradações de força pós-repouso nos músculos de camundongos LMI. Além disso, a Ry bloqueou a degradação ou potenciação de PRC observada em camundongos LMI e C; o Li+ inibiu o NCX e converteu a degradação em potenciação de CPR em camundongos LMI. Embora os camundongos MMI e LMI tenham apresentado diminuição no SERCA2 (72 ± 7% e 47 ± 9% de camundongos controle, respectivamente) e expressão protéica de fosfo-Ser16-PLB (75 ± 5% e 46 ± 11%, respectivamente), a superexpressão do NCX (175 ± 20%) só foi observada nos músculos de camundongos LMI. CONCLUSÃO: Nossos resultados mostraram, pela primeira vez, que a remodelação miocárdica pós-IAM em camundongos pode mudar a potenciação regular para degradação pós-repouso, afetando as proteínas de manipulação de Ca(2+) em miócitos.


BACKGROUND: Post-rest contraction (PRC) of cardiac muscle provides indirect information about the intracellular calcium handling. OBJECTIVE: Our aim was to study the behavior of PRC, and its underlying mechanisms, in rats with myocardial infarction. METHODS: Six weeks after coronary occlusion, the contractility of papillary muscles (PM) obtained from sham-operated (C, n=17), moderate infarcted (MMI, n=10) and large infarcted (LMI, n=14) rats was evaluated, following rest intervals of 10 to 60 seconds before and after incubation with lithium chloride (Li+) substituting sodium chloride or ryanodine (Ry). Protein expression of SR Ca(2+)-ATPase (SERCA2), Na+/Ca2+ exchanger (NCX), phospholamban (PLB) and phospho-Ser(16)-PLB were analyzed by Western blotting. RESULTS: MMI exhibited reduced PRC potentiation when compared to C. Opposing the normal potentiation for C, post-rest decays of force were observed in LMI muscles. In addition, Ry blocked PRC decay or potentiation observed in LMI and C; Li+ inhibited NCX and converted PRC decay to potentiation in LMI. Although MMI and LMI presented decreased SERCA2 (72±7% and 47±9% of Control, respectively) and phospho-Ser16-PLB (75±5% and 46±11%, respectively) protein expression, overexpression of NCX (175±20%) was only observed in LMI muscles. CONCLUSION: Our results showed, for the first time ever, that myocardial remodeling after MI in rats may change the regular potentiation to post-rest decay by affecting myocyte Ca(2+) handling proteins.


FUNDAMENTO: La Contracción pos pausa (CPP) del músculo cardíaco provee informaciones indirectas sobre la manejo del calcio intracelular. OBJETIVO: Nuestro objetivo fue estudiar el comportamiento de la CPP y sus mecanismos subyacentes en Ratas con infarto de miocardio. MÉTODOS: Seis semanas después de la oclusión coronaria, la contractilidad de los Músculos Papilares (MP) obtenidos a partir de Ratas sometidos a falsa cirurgia (C, n = 17), con infarto moderado (MMI, n = 10) y gran infarto (LMI, n = 14), fue evaluada después de pausas de estímulos de 10 a 60 segundos antes y después de la incubación con cloruro de litio (Li+) en substitución del cloruro de sodio o rianodina (Ry). La expresión proteica de SR Ca(2+)-ATPasa (SERCA2), intercambiador Na+/Ca2+ (NCX), fosfolamban (PLB) y fosfo-Ser (16)-PLB fue analizada por Western blotting. RESULTADOS: Los Ratas MMI presentaron potenciación de CPP reducida en comparación a los Ratas C. En oposición a la potenciación normal para Ratas C, fueron observadas decaimientos de fuerza post-reposo en los músculos de Ratas LMI. Además de eso, la Ry bloqueó la decaimiento o potenciación de PRC observada en Ratas LMI y C; el Li+ inhibió el NCX y convirtió la decaimiento en potenciación de CPP en Ratas LMI. Aunque los Ratas MMI y LMI hayan presentado disminución en el SERCA2 (72 ± 7% y 47 ± 9% de Ratas control, respectivamente) y expresión proteica de fosfo-Ser16-PLB (75 ± 5% y 46 ± 11%, respectivamente), la superexpresión del NCX (175 ± 20%) sólo fue observada en los músculos de Ratas LMI. CONCLUSIÓN: Nuestros resultados mostraron, por primera vez, que el remodelado miocárdico post-IAM en Ratas puede cambiar la potenciación regular para decaimiento post-reposo, afectando las proteínas de manejo del Ca(2+) en miocitos.


Assuntos
Animais , Ratos , Proteínas de Ligação ao Cálcio/metabolismo , Cálcio/metabolismo , Contração Miocárdica/efeitos dos fármacos , Infarto do Miocárdio/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo , Trocador de Sódio e Cálcio/metabolismo , Remodelação Ventricular/fisiologia , Modelos Animais de Doenças , Cloreto de Lítio/farmacologia , Contração Miocárdica/fisiologia , Infarto do Miocárdio/classificação , Miócitos Cardíacos/metabolismo , Músculos Papilares/metabolismo , Distribuição Aleatória , Ratos Wistar , Rianodina/farmacologia
11.
Chinese Journal of Pathology ; (12): 475-478, 2012.
Artigo em Chinês | WPRIM | ID: wpr-303544

RESUMO

<p><b>OBJECTIVE</b>To assess the effects of LiCl on prostate cancer growth and to explore the underlying mechanisms.</p><p><b>METHODS</b>Effects of LiCl on cell growth in vitro and in vivo were determined by cell counting and xenografts of prostate cancer cells. Alterations in cell proliferation and the expression of DNA replication-related protein were determined by MTT assay, BrdU incorporation and Western blot.</p><p><b>RESULTS</b>Compared to PBS control group, the number of prostate cancer cells (PC-3) were lower treated with 10 mmol/L LiCl, the number was 1.9×10(5), 4.8×10(5) and the difference was significant (P < 0.05). The inhibition rate of cellular proliferation were 50%, 95% and 98%, respectively, in LiCl group, NaCl and KCl control group, the difference was significant (P < 0.05). The A-Value of BrdU incorporation was 1.5, 1.3 treated with 10 mmol/L, 30 mmol/L LiCl, while the A-value of BrdU incorporation was 4 in PBS control group, the difference was significant (P < 0.05). On the protein level, LiCl downregulates expression of cdc 6, cyclins A and cyclins E, and cdc 25C, and upregulates expression of the CDK inhibitor p21(CIP1). The mean volume and weight of xenograft tumor were 50 mm(3) and 296 mg after LiCl intraperitoneal injection, But PBS control group were 180 mm(3) and 957 mg, the difference was significant (P < 0.05).</p><p><b>CONCLUSION</b>LiCl disrupts DNA replication and suppresses tumor growth of prostate cancer cells in vitro and in vivo.</p>


Assuntos
Animais , Humanos , Masculino , Camundongos , Antineoplásicos , Farmacologia , Proteínas de Ciclo Celular , Metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Ciclina A , Metabolismo , Ciclina E , Metabolismo , Inibidor de Quinase Dependente de Ciclina p21 , Metabolismo , Replicação do DNA , Cloreto de Lítio , Farmacologia , Camundongos Endogâmicos BALB C , Camundongos Nus , Transplante de Neoplasias , Proteínas Nucleares , Metabolismo , Neoplasias da Próstata , Metabolismo , Patologia , Carga Tumoral , Fosfatases cdc25 , Metabolismo
12.
Acta Physiologica Sinica ; (6): 639-645, 2012.
Artigo em Chinês | WPRIM | ID: wpr-333160

RESUMO

This study was undertaken to observe the effect of acute stress on seizure occurrence in chronic period of epileptic model rats. Lithium-pilocarpine (LiCl-PILO)-induced epileptic rat model was constructed. At the spontaneous recurrent seizure period, acute stress stimulations such as cat's urine and foot electrical shock were applied to observe the behavioral changes and seizure occurrence. The results showed that after the cat's urine stimulation, the self-directed behaviors of the epileptic model rats decreased significantly, while the risk assessment behaviors increased significantly. The seizure occurrence, however, was not observed during the 45 min after the stimulation. Applying electrical foot shocks also did not evoke seizures in epileptic model rats. On the contrast, intra-peritoneal injection of low dose of pentylenetetrazole (PTZ, 30 mg/kg) evoked seizure more efficiently, and the duration of seizure activity was extensively prolonged in epileptic model rats than that of control rats. Taken together, these results indicate that although applying stress stimulations such as cat's urine and electrical foot shock cause several behavioral changes, they are not severe enough to evoke seizure in epileptic model rats.


Assuntos
Animais , Ratos , Comportamento Animal , Modelos Animais de Doenças , Epilepsia , Cloreto de Lítio , Pentilenotetrazol , Pilocarpina , Convulsões , Estresse Fisiológico
13.
Journal of Experimental Hematology ; (6): 654-657, 2012.
Artigo em Chinês | WPRIM | ID: wpr-263329

RESUMO

Wnt signaling has been shown to inhibit adipogenic differentiation while inducing the osteogenic pathway of bone marrow stromal cells (BMSC). Patients with aplastic anemia (AA) often show excess fat accumulation in the bone marrow, possibly due to overactivation of the adipogenic pathway. Therefore, an activator of the Wnt signaling may alleviate the symptoms by enhancing the inhibition on the differentiation of BMSC towards adipocytes. To judge this hypothesis, the therapeutic effects of Wnt signaling activator lithium chloride (LiCl) combined with the currently used immunosuppressor cyclosporine A (CsA) on mice with AA in vivo was investigated. Mouse model with AA was established and the disease was confirmed by increased fat cell counts and decreased hematopoietic cell counts in the bone marrow of these animals. These mice treated with CsA 50 mg/(kg·d) alone or together with LiCl 20 mg/(kg·d), once daily for 5 d, then at day 14, 21 and 28 after establishment of mouse model with AA, the treatment effects were observed, including peripheral blood cells, bone marrow mononuclear cells (BMMNC) count and bone marrow biopsy examination in each group. The results showed that compared with the AA group, Hb content, WBC and BMMNC counts of CsA group and the combination group significantly increased. HE staining of bone marrow biopsy sample showed that the fat cells were significantly reduced in the bone marrow cavity (P < 0.05). Compared with the CsA group, Hb content, WBC and BMMNC counts of the combination group significantly increased (P < 0.05); HE staining of bone marrow biopsy sample showed that fat cells were reduced, the hematopoiesis of bone marrow was close to the normal. It is concluded that Wnt signal activator (LiCl) combined with CsA displayed a better treatment effect on AA in mouse models than the effect of using CsA only. They can promote the hematopoietic function of bone marrow, which may correlate with inhibiting differentiation of bone marrow mesenchymal stem cells into the fat cells by Wnt signaling.


Assuntos
Animais , Feminino , Camundongos , Anemia Aplástica , Tratamento Farmacológico , Metabolismo , Exame de Medula Óssea , Ciclosporina , Usos Terapêuticos , Modelos Animais de Doenças , Quimioterapia Combinada , Cloreto de Lítio , Usos Terapêuticos , Camundongos Endogâmicos BALB C , Via de Sinalização Wnt
14.
IJRM-Iranian Journal of Reproductive Medicine. 2012; 10 (3): 223-228
em Inglês | IMEMR | ID: emr-144282

RESUMO

Main function of corpus luteum is progesterone synthesis that is significantly accompanied with an increase in levels of mRNA encoding of steroidogenic enzymes known as luteal markers. This study was designed to evaluate effects of lithium chloride on the release of steroid hormones and steroidogenic enzymes in gonadotropin-stimulated rats. Immature 23 days old Wistar rats were divided into 10 groups; each group comprised of 8 rats, and induced with single injection of pregnant mare's serum gonadotrophin [PMSG] and followed by single injection of human chorionic gonadotropin [hCG]. Then, rats were given lithium chloride [LiCl] or saline at 12 hours post-hCG injection. Ovaries were collected in 4-hour interval from 8-24 hour post-hCG injection. Expression pattern of steroidogenic acute regulatory protein [StAR], side-chain cleavage cytochrome P450 [P450scc] and 3beta-hydroxysteroid dehydrogenase [3beta-HSD] genes were determined by semi-quantitative RT-PCR. In addition, serum levels of progesterone and 17beta-estradiol were measured by ELISA. Our results showed that hCG stimulation of progesterone was markedly diminished and transcript levels of key steroidogenic enzymes were altered in the hormone-stimulated rats following LiCl treatment. These results suggest that critical steps in the function of corpus luteum are disrupted by lithium. It is concluded that LiCl is an effective factor for suppressing of steroid genes expression


Assuntos
Animais , Feminino , Progesterona/biossíntese , Corpo Lúteo/efeitos dos fármacos , Cloreto de Lítio , Ratos Wistar , Estradiol
15.
Journal of Gynecologic Oncology ; : 225-232, 2011.
Artigo em Inglês | WPRIM | ID: wpr-101758

RESUMO

OBJECTIVE: The aim of the study was to investigate whether lithium chloride and medroxyprogesterone acetate can potentiate the cytotoxicity of imatinib mesylate in human endometrial cancer in vitro and the effect of midkine in these therapies. METHODS: Imatinib mesylate (50 microM), lithium chloride (100 microM), medroxyprogesterone acetate (200 microM) and their combination were applied to monolayer and three dimensional cultures of human Ishikawa endometrial cancer for 72 hours. The cell proliferation index, apoptotic index, caspase-3 and midkine levels, cell cycle distributions in monolayer cultures and cell ultrastructure in spheroid cultures were evaluated. Results were statistically analyzed using the Student's t-test. RESULTS: All drug applications inhibited cell proliferation (p<0.05), however the combination were the effective groups for 72 hours (p<0.05). Interestingly, although the loss of efficiency was seen higly seen every 24 hours at single applications, the inhibition rates of the combination groups were almost same for 72 hours. In concordance with these results, the apoptotic index, caspase-3 levels (p<0.05), cell morphology and ultrastructure damages were much higher in the combination groups. Imatinib mesylate induced S-phase arrest, however other groups induced G0+G1-phase arrest at 24 hours and all groups induced G0+G1 arrest at 72 hours (p<0.05). Imatinib mesylate and imatinib mesylate with medroxyprogesterone acetate induced highest decrease in midkine levels, respectively (p<0.05). CONCLUSION: The present study showed that the combination of imatinib mesylate with lithium chloride and medroxyprogesterone acetate is highly active in Ishikawa endometrial carcinoma in vitro and the inhibition of midkine involved in their mechanism of action against endometrium defense.


Assuntos
Feminino , Humanos , Benzamidas , Caspase 3 , Ciclo Celular , Proliferação de Células , Citocinas , Neoplasias do Endométrio , Endométrio , Mesilato de Imatinib , Lítio , Cloreto de Lítio , Medroxiprogesterona , Acetato de Medroxiprogesterona , Mesilatos , Piperazinas , Pirimidinas
16.
Biol. Res ; 44(4): 377-382, 2011. ilus, tab
Artigo em Inglês | LILACS | ID: lil-626738

RESUMO

In China, Monascus spp., a traditional fungus used in fermentation, is used as a natural food additive. Monascus spp. can produce a secondary metabolite, monacolin K namely, which is proven to be a cholesterol-lowering and hypotensive agent. Hence, recently, many researchers have begun focusing on how to increase the production of monacolin K by Monascus purpureus. In the present study, we investigated the effect of the fungal elicitor and the mutagenesis of UV & LiCl on the amount of monacolin K produced by Monascus purpureus. The fugal elicitor, Sporobolomyces huaxiensis, was isolated from tea leaves and its filtrate was added into the culture filtrate of Monascus purpureus during growth to induct the production of monacolin K. The results showed that the highest amount of monacolin K produced by the liquid fermentation was 446.92 mg/mL, which was produced after the fungal elicitor was added to the culture filtrate of Monascus purpureus on the day 4; this amount was approximately 6 times greater than that of the control culture filtrate, whereas the highest amount of monacolin K produced by the mutated strain was 3 times greater than the control culture after the irradiation of UV light in the presence of 1.0 % LiCl in the medium.


Assuntos
Basidiomycota/fisiologia , Lovastatina/biossíntese , Mutação , Monascus/metabolismo , China , Meios de Cultura , Cloreto de Lítio , Monascus/genética , Monascus/efeitos da radiação , Raios Ultravioleta
17.
Chinese Medical Journal ; (24): 2410-2415, 2010.
Artigo em Inglês | WPRIM | ID: wpr-237440

RESUMO

<p><b>BACKGROUND</b>Annexin A7 (synexin, ANXA7) is a member of annexins, which plays an essential role in the regulation of calcium homeostasis. Considerable evidence shows that the pathogenetic mechanism of acquired epilepsy (AE) has been related to the imbalance of calcium homeostasis. The aim of this study was to investigate ANXA7 expression and cellular localization in the cortex and hippocampus in the rat lithium-pilocarpine model of AE.</p><p><b>METHODS</b>Totally 81 adult healthy male Wistar rats were randomly divided into control group (n = 9) and experimental group (n = 72), the experimental group contained eight subgroups according to sacrifice time (n = 9) (6-hour, 24-hour, 48-hour, 72-hour, 7-day, 15-day, 1-month, and 2-month). In the experimental group, rats were intraperitoneally injected by lithium-pilocarpine to induce AE model. We examined the expression and localization of ANXA7 via immunohistochemistry, double-label immunofluorescence with the use of neuron specific enolase (NSE) antibody, glial fibrillary acidic protein (GFAP) antibody and propidium iodide (PI), respectively. The data of optical density value were analyzed by analysis of variance.</p><p><b>RESULTS</b>ANXA7 expression increased significantly in the experimental groups especially in the acute period (6 hours, 24 hours, and 48 hours after the onset of seizure) using immunohistochemistry. Double-label immunofluorescence and confocal microscopy disclosed that ANXA7 localized in the neurons but not in astrocytes and did not localize in the nucleus, which were performed with anti-NSE, anti-GFAP and PI respectively.</p><p><b>CONCLUSION</b>ANXA7 may play a potential role in the pathogenetic mechanisms of the rat lithium-pilocarpine model of AE.</p>


Assuntos
Animais , Masculino , Ratos , Anexina A7 , Fisiologia , Cálcio , Metabolismo , Córtex Cerebral , Química , Modelos Animais de Doenças , Imunofluorescência , Hipocampo , Química , Imuno-Histoquímica , Cloreto de Lítio , Pilocarpina , Ratos Wistar , Estado Epiléptico , Metabolismo
18.
Journal of Southern Medical University ; (12): 2436-2439, 2010.
Artigo em Chinês | WPRIM | ID: wpr-323642

RESUMO

<p><b>OBJECTIVE</b>To observe the effects of lithium chloride combined with human umbilical cord blood mesenchymal stem cell (hUCB-SCs) transplantation in the treatment of spinal cord injury in rats.</p><p><b>METHODS</b>Eighty female SD rats with complete T9 spinal cord transaction were randomized into 4 groups (n=20), namely the control group (group A), lithium chloride group (group B), hUCB-SCs group (group C) and hUCB-SCs(+) lithium chloride group (group D). On days 1 and 3 and the last days of the following weeks postoperatively, the motor function of the hindlimb of the rats were evaluated according to the BBB scores. At 8 weeks, all the rats were sacrificed and the spinal cords were taken for morphological observation. The spinal cord tissues at the injury site were observed with Brdu nuclear labeling to identify the survival and migration of the transplanted SCs. The regeneration and distribution of the spinal nerve fibers were observed with fluorescent-gold (FG) spinal cord retrograde tracing.</p><p><b>RESULTS</b>Brdu labeling showed that the transplanted hUCB-SCs survived and migrated in the spinal cord 8 weeks postoperatively in groups C and D. FG retrograde tracing identified a small amount of pyramidal cells that migrated across the injury site in groups C and D. The BBB scores of the hindlimb motor function 8 weeks postoperatively were 4.11∓0.14, 4.50∓0.15, 8.31∓0.11 and 11.15∓0.18 in groups A, B, C and D, respectively.</p><p><b>CONCLUSION</b>Lithium chloride can promote the survival and differentiation of hUCB-SCs into neural cells at the injury site. Lithium chloride combined with hUCB-SCs transplantation may accelerate functional recovery of the hindlimbs in rats with complete transection of the spinal cord.</p>


Assuntos
Animais , Feminino , Humanos , Ratos , Transplante de Células-Tronco de Sangue do Cordão Umbilical , Cloreto de Lítio , Usos Terapêuticos , Traumatismos da Medula Espinal , Terapêutica
19.
Journal of Central South University(Medical Sciences) ; (12): 329-334, 2010.
Artigo em Chinês | WPRIM | ID: wpr-814446

RESUMO

OBJECTIVE@#To investigate the role of phosphorylation of glycogen synthase kinase-3beta (GSK-3beta) inducing epithelial mesenchymal transition in human peritoneal mesothelial cells (HPMC).@*METHODS@#Primary HPMC was harvested from human omental tissue and maintained under defined in vitro conditions. The expression of p-GSK-3beta and total GSK-3beta in HMPC was detected by Western blot after incubation with different concentrations (0, 5, 10, 20, and 40 mmol/L)of LiCl at different time points (0, 1, 3, 6, and 12 h). The protein expression of E-cadherin and alpha-SMA was also examined after treatment with 20 mmol/L LiCl according to different time courses. The intracellular distribution and expression of alpha-SMA were determined by indirect immunofluorescence.@*RESULTS@#LiCl stimulated phosphorylation of GSK-3beta and the effect was time-dependent and concentration-dependent to limited extent (P<0.05). The expression of alpha-SMA increased (P<0.05) and the expression of E-cadherin decreased significantly (P<0.05) after 24 h stimulation by 20 mmol/L LiCl. The indirect immunoflurescence showed that the expression of alpha-SMA in HPMC increased significantly after 24 h incubation with 20 mmol/L LiCl.@*CONCLUSION@#The phosphorylation of GSK-3beta leads HMPC to epithelial mesenchymal transition and provides new clue for the treatment of peritoneal fibrosis.


Assuntos
Humanos , Actinas , Metabolismo , Caderinas , Metabolismo , Células Epiteliais , Biologia Celular , Transição Epitelial-Mesenquimal , Quinase 3 da Glicogênio Sintase , Metabolismo , Glicogênio Sintase Quinase 3 beta , Cloreto de Lítio , Farmacologia , Mesoderma , Biologia Celular , Peritônio , Biologia Celular , Fosforilação
20.
Braz. J. Psychiatry (São Paulo, 1999, Impr.) ; 30(3): 215-221, set. 2008. graf, tab
Artigo em Inglês | LILACS | ID: lil-493775

RESUMO

OBJECTIVE: Lithium has been successfully employed to treat bipolar disorder for decades, and recently, was shown to attenuate the symptoms of other pathologies such as Alzheimer's disease, Down's syndrome, ischemic processes, and glutamate-mediated excitotoxicity. However, lithium's narrow therapeutic range limits its broader use. Therefore, the development of methods to better predict its dose becomes essential to an ideal therapy. METHOD: the performance of adult Wistar rats was evaluated at the open field and elevated plus maze after a six weeks treatment with chow supplemented with 0.255 percent, or 0.383 percent of lithium chloride, or normal feed. Thereafter, blood samples were collected to measure the serum lithium concentration. RESULTS: Animals fed with 0.255 percent lithium chloride supplemented chow presented a higher rearing frequency at the open field, and higher frequency of arms entrance at the elevated plus maze than animals fed with a 50 percent higher lithium dose presented. Nevertheless, both groups presented similar lithium plasmatic concentration. DISCUSSION: different behaviors induced by both lithium doses suggest that these animals had different lithium distribution in their brains that was not detected by lithium serum measurement. CONCLUSION: serum lithium concentration measurements do not seem to provide sufficient precision to support its use as predictive of behaviors.


OBJETIVO: Além de ser usado há décadas para tratar distúrbio bipolar, o lítio, mais recentemente, demonstrou-se eficaz para Alzheimer, síndrome de Down, processos isquêmicos e excitotoxicidade mediada por glutamato. Contudo, a estreita janela terapêutica do lítio limita seu uso. Portanto, o estabelecimento de métodos preditivos de dose torna-se importante. MÉTODO: O desempenho de ratos Wistar adultos foi avaliado no campo aberto e labirinto em cruz elevado após seis semanas de tratamento com uma ração suplementada com 0,255 por cento ou 0,383 por cento de cloreto de lítio ou ração normal. Coletou-se amostras de sangue para dosagem plasmática do lítio. RESULTADOS: Os animais alimentados com a ração com 0,255 por cento de cloreto de lítio fizeram mais rearing no campo aberto e tiveram uma maior freqüência de entradas nos braços do labirinto elevado que os animais que ingeriram a dose mais alta. Apesar disso, verificou-se níveis plasmáticos de lítio semelhantes em ambos os grupos. DISCUSSÃO: A variação nos comportamentos destarte a presença de níveis plasmáticos semelhantes sugere que as diferentes doses produziram diferentes concentrações cerebrais não detectadas pela medida plasmática. CONCLUSÃO: Medidas da concentração plasmática de lítio não permitem prever de forma completa seus efeitos comportamentais.


Assuntos
Animais , Feminino , Masculino , Ratos , Antimaníacos/administração & dosagem , Transtorno Bipolar/tratamento farmacológico , Encéfalo/metabolismo , Cloreto de Lítio/administração & dosagem , Aprendizagem em Labirinto/efeitos dos fármacos , Análise de Variância , Antimaníacos/sangue , Transtorno Bipolar/sangue , Cloreto de Lítio/sangue , Ratos Wistar
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