Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 27
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
Mol Genet Metab Rep ; 36: 100980, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37275240

RESUMO

Gaucher disease (GD) is caused by biallelic pathogenic variants in GBA1 gene that encodes the lysosomal enzyme glucocerebrosidase. Up to now, specific treatment for GD cannot completely reverse bone complications. Bone is composed of different cell types; including osteoblasts, osteocytes and osteoclasts. Osteoblasts are present on bone surfaces and are derived from local mesenchymal stem cells (MSCs). Depending on environment conditions, MSCs could differentiate into osteoblasts and adipocytes. Mature adipocytes-secreted adipokines and free fatty acids affect both osteoblasts and osteoclasts formation/activity and therefore mediate skeletal homeostasis. The aim of this study was to evaluate possible alterations in GD adipocyte (GD Ad) that could contribute to bone complications. MSCs were grown in adipogenic media in order to evaluate expression of differentiation markers as PPAR-γ. PPAR-γ was observed into the nucleus of GD Ad, indicating that these cells are properly stimulated. However, these cells accumulate lesser lipid droplets (LDs) than Control Ad. In order to study lipid droplet metabolism, we evaluated the lipolysis of these structures by the measurement of free glycerol in culture supernatant. Our results indicated that GD Ad had an alteration in this process, evidenced by an increase in glycerol release. We have also evaluated two enzymes involved in LDs synthesis: fatty acid synthase (FASN) and stearoyl-coenzyme A desaturase 1 (SCD1). The transcription of these genes was decreased in GD Ad, suggesting a dysfunction in the synthesis of LDs. In conclusion, our results show an alteration in LDs metabolism of GD Ad, independent of adipocyte differentiation process. This alteration would be caused by an increase in lipolysis in early stages of differentiation and also by a reduction of lipid synthesis, which could contribute with the skeletal imbalance in GD.

2.
J Mech Behav Biomed Mater ; 123: 104741, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34461399

RESUMO

Biomedical Co-29Cr-6Mo alloy is one of the alloys that are suitable for laser powder bed fusion (LPBF) additive manufacturing and as an implant material is often used in situations of critical and cyclic loading. Thus, fatigue crack growth (FCG) behaviour and resistance of the alloy processed by LPBF are an important consideration for dental and orthopaedic applications. In this study, FCG testing has been conducted to evaluate how build direction (BD) dependent grain/cell structure in relation to crack growth direction (CD), either CD⊥BD or CD//BD, affects FCG behaviour. It has been found that the threshold stress intensity factor (ΔKTh) value is significantly higher and the values of c and m in Paris equation are slightly lower for CD//BD samples than the values for CD⊥BD samples, respectively. Failure analysis has revealed that the effects of the commonly known defect, lack of fusion, on both ΔKTh and FCG rate are weak. It has been identified that crack has mainly propagated in a transgranular and transcellular manner, consistent with the observation of the crack path being more torturous and with the higher crack growth resistance determined in CD//BD samples than in CD⊥BD samples. This will be further discussed linking the difference in the size of crack segment, which is BD and thus grain/cell length dependent, to the roughness-induced crack closure mechanism.


Assuntos
Ligas , Lasers , Fadiga , Humanos , Pós
3.
Mol Genet Metab ; 132(2): 76-85, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32782168

RESUMO

Gaucher disease (GD) is caused by pathogenic mutations in GBA1, the gene that encodes the lysosomal enzyme ß-glucocerebrosidase. Despite the existence of a variety of specific treatments for GD, they cannot completely reverse bone complications. Many studies have evidenced the impairment in bone tissue of GD, and molecular mechanisms of bone density alterations in GD are being studied during the last years and different reports emphasized its efforts trying to unravel why and how bone tissue is affected. The cause of skeletal density affection in GD is a matter of debates between research groups. and there are two opposing hypotheses trying to explain reduced bone mineral density in GD: increased bone resorption versus impaired bone formation. In this review, we discuss the diverse mechanisms of bone alterations implicated in GD revealed until the present, along with a presentation of normal bone physiology and its regulation. With this information in mind, we discuss effectiveness of specific therapies, introduce possible adjunctive therapies and present a novel model for GD-associated bone density pathogenesis. Under the exposed evidence, we may conclude that both sides of the balance of remodeling process are altered. In GD the observed osteopenia/osteoporosis may be the result of contribution of both reduced bone formation and increased bone resorption.


Assuntos
Densidade Óssea/genética , Osso e Ossos/metabolismo , Doença de Gaucher/metabolismo , Glucosilceramidase/genética , Osso e Ossos/patologia , Diferenciação Celular/genética , Doença de Gaucher/genética , Doença de Gaucher/patologia , Humanos , Lisossomos/enzimologia , Lisossomos/genética
5.
Mol Genet Metab ; 130(4): 274-282, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32536424

RESUMO

Gaucher disease (GD) is caused by pathogenic mutations in GBA1, the gene that encodes the lysosomal enzyme ß-glucocerebrosidase. Until now, treatments for GD cannot completely reverse bone problems. The aim of this work was to evaluate the potential of MSCs from GD patients (GD MSCs) to differentiate towards the osteoblast (GD Ob) and adipocyte (GD Ad) lineages, and their role in osteoclastogenesis. We observed that GD Ob exhibited reduced mineralization, collagen deposition and alkaline phosphatase activity (ALP), as well as decreased gene expression of RUNX2, COLA1 and ALP. We also evaluated the process of osteoclastogenesis and observed that conditioned media from GD MSCs supernatants induced an increase in the number of osteoclasts. In this model, osteoclastogenesis was induced by RANKL and IL-1ß. Furthermore, results showed that in GD MSCs there was a promotion in NLRP3 and PPAR-γ gene expression. Adipogenic differentiation revealed that GD Ad had an increase in PPAR-γ and a reduced RUNX2 gene expression, promoting adipocyte differentiation. In conclusion, our results show that GD MSCs exhibited deficient GD Ob differentiation and increased adipogenesis. In addition, we show that GD MSCs promoted increased osteoclastogenesis through RANKL and IL-1ß. These changes in GD MSCs are likely to contribute to skeletal imbalance observed in GD patients.


Assuntos
Adipogenia , Diferenciação Celular , Doença de Gaucher/patologia , Glucosilceramidase/deficiência , Células-Tronco Mesenquimais/patologia , Osteoclastos/patologia , Osteogênese , Apoptose , Ciclo Celular , Células Cultivadas , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Doença de Gaucher/metabolismo , Regulação da Expressão Gênica , Humanos , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Células-Tronco Mesenquimais/metabolismo , Osteoclastos/metabolismo , PPAR gama/genética , PPAR gama/metabolismo , Ligante RANK/genética , Ligante RANK/metabolismo
6.
Bone ; 103: 262-269, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28736246

RESUMO

Gaucher disease (GD) is caused by mutations on the gene encoding for the lysosomal enzyme glucocerebrosidase. Type I GD (GD1) patients present anemia, hepatosplenomegaly and bone alterations. In spite of treatment, bone alterations in GD patients persist, including poor bone mineral density (BMD). Mechanisms leading to bone damage are not completely understood, but previous reports suggest that osteoclasts are involved. Chitotriosidase (CHIT) is the most reliable biomarker used in the follow up of patients, although its correlation with bone status is unknown. The aim of this work was to study the pro-osteoclastogenic potential in patients and to evaluate its correlation with CHIT activity levels and clinical parameters. PBMCs from treated patients and healthy controls were cultured in the presence of M-CSF, and mature osteoclasts were counted. BMD, blood CHIT activity and serum levels of CTX, BAP, and cytokines were evaluated in patients. We found that blood CHIT activity and osteoclast differentiation were significantly increased in patients, but no correlation between them was observed. Interestingly, osteoclast numbers but not CHIT, presented a negative correlation with BMD expressed as Z-score. CTX, BAP and serum cytokines involved in bone remodeling were found altered in GD1 patients. These results show for the first time a correlation between osteoclast differentiation and BMD in GD1 patients, supporting the involvement of osteoclasts in the bone pathology of GD1. Our results also suggest that an altered immune response may play an important role in bone damage.


Assuntos
Doença de Gaucher/enzimologia , Doença de Gaucher/patologia , Hexosaminidases/sangue , Osteoclastos/patologia , Adolescente , Adulto , Densidade Óssea , Diferenciação Celular , Células Cultivadas , Criança , Pré-Escolar , Citocinas/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
7.
Infect Immun ; 81(7): 2371-8, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23630952

RESUMO

The exacerbated induction of innate immune responses in airways can abrogate diverse lung infections by a phenomenon known as stimulated innate resistance (StIR). We recently demonstrated that the enhancement of innate response activation can efficiently impair Bordetella pertussis colonization in a Toll-like receptor 4 (TLR4)-dependent manner. The aim of this work was to further characterize the effect of lipopolysaccharide (LPS) on StIR and to identify the mechanisms that mediate this process. Our results showed that bacterial infection was completely abrogated in treated mice when the LPS of B. pertussis (1 µg) was added before (48 h or 24 h), after (24 h), or simultaneously with the B. pertussis challenge (10(7) CFU). Moreover, we detected that LPS completely cleared bacterial infection as soon as 2 h posttreatment. This timing suggests that the observed StIR phenomenon should be mediated by fast-acting antimicrobial mechanisms. Although neutrophil recruitment was already evident at this time point, depletion assays using an anti-GR1 antibody showed that B. pertussis clearance was achieved even in the absence of neutrophils. To evaluate the possible role of free radicals in StIR, we performed animal assays using the antioxidant N-acetyl cysteine (NAC), which is known to inactivate oxidant species. NAC administration blocked the B. pertussis clearance induced by LPS. Nitrite concentrations were also increased in the LPS-treated mice; however, the inhibition of nitric oxide synthetases did not suppress the LPS-induced bacterial clearance. Taken together, our results show that reactive oxygen species (ROS) play an essential role in the TLR4-dependent innate clearance of B. pertussis.


Assuntos
Infecções por Bordetella/imunologia , Bordetella pertussis/patogenicidade , Imunidade Inata , Espécies Reativas de Oxigênio/imunologia , Acetilcisteína/administração & dosagem , Acetilcisteína/farmacologia , Animais , Carga Bacteriana , Infecções por Bordetella/microbiologia , Bordetella pertussis/efeitos dos fármacos , Bordetella pertussis/imunologia , Guanidinas/farmacologia , Lipopolissacarídeos/imunologia , Lipopolissacarídeos/farmacologia , Pulmão/imunologia , Pulmão/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/metabolismo , Nitritos/metabolismo , Fatores de Tempo , Receptor 4 Toll-Like/imunologia
8.
Epidemiol Infect ; 141(4): 718-34, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22874088

RESUMO

Due to the current epidemiological situation of pertussis, several countries have implemented vaccination strategies that include a booster dose for adolescents. Since there is still no evidence showing that the adolescent booster has a positive effect on the most vulnerable group represented by infants, it is difficult to universalize the recommendation to include such reinforcement. In this work we present an age-structured compartmental deterministic model that considers the outstanding epidemiological features of the disease in order to assess the impact of the booster dose at age 11 years (Tdap booster) to infants. To this end, we performed different parameterizations of the model that represent distinct possible epidemiological scenarios. The results obtained show that the inclusion of a single Tdap dose at age 11 years significantly reduces the incidence of the disease within this age group, but has a very low impact on the risk group (0-1 year). An effort to improve the coverage of the first dose would have a much greater impact on infants. These results hold in the 18 scenarios considered, which demonstrates the robustness of these conclusions.


Assuntos
Imunização Secundária/estatística & dados numéricos , Vacina contra Coqueluche/uso terapêutico , Coqueluche/transmissão , Adolescente , Argentina/epidemiologia , Criança , Humanos , Esquemas de Imunização , Lactente , Modelos Teóricos , Coqueluche/epidemiologia , Coqueluche/prevenção & controle
9.
Med. paliat ; 12(1): 3-5, ene.-mar. 2005.
Artigo em Es | IBECS | ID: ibc-040092

RESUMO

El fenómeno de la inmigración también ha irrumpido en el campo delos Cuidados Paliativos presentando nuevos retos. Los objetivos de este artículo son analizar, a partir de un caso, los problemas específicos que encontramos al trabajar con población inmigrante irregular con enfermedad avanzada y/o terminal y conocer el marco legal que nos ampara y que rige este tipo de intervenciones (AU)


The immigration phenomenon has also bursted into the Palliative Care area presenting new challenges. The aims of this article are to analyse, from a case report, the specific problems we find while working with irregular immigrants who have an advanced and/or terminal disease and to know the legal frame that protects us and governs this kind of interventions (AU)


Assuntos
Masculino , Pessoa de Meia-Idade , Humanos , Cuidados Paliativos/estatística & dados numéricos , Emigração e Imigração/estatística & dados numéricos , Apoio Social , Atenção à Saúde/legislação & jurisprudência , Doente Terminal , Repatriação , Atestado de Óbito , Neoplasias Gástricas
10.
Pharmacol Biochem Behav ; 68(1): 125-33, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11274717

RESUMO

Antidepressants are used in the treatment of a variety of pain syndromes. Most of them act by blocking noradrenaline (NA) and serotonin (5-HT) reuptake. It is also well known that the serotonergic system is also involved in calcitonin (CT) analgesia. Taking these two evidences into account, the modification of the analgesic effect of nortriptyline, amitriptyline, and paroxetine in the presence of salmon CT (s-CT) was examined in mice. The forced-swimming test was carried out in order to choose doses of each drug that did not induce an antidepressant effect under our experimental conditions (nortriptyline: 0.2-5 mg/kg ip, amitriptyline: 2.5-20 mg/kg ip, and paroxetine: 5-30 mg/kg ip). The analgesic effect of each antidepressant was then evaluated using the acetic acid test. At the doses tested, the antidepressants induced a dose-dependent analgesic effect. When mice were pre-treated with a subanalgesic dose of s-CT (2.5 IU/kg), the analgesic effect of amitriptyline and paroxetine was significantly increased though no modification was found for nortriptyline. In summary, s-CT was able to increase the analgesic effect of the antidepressant drugs that reduce the uptake of 5-HT, suggesting that the joint administration of antidepressants and CT may be an interesting alternative in pain management.


Assuntos
Analgésicos/farmacologia , Antidepressivos/farmacologia , Calcitonina/farmacologia , Inibidores da Captação Adrenérgica/farmacologia , Amitriptilina/farmacologia , Animais , Antidepressivos Tricíclicos/farmacologia , Química Encefálica/efeitos dos fármacos , Depressão/tratamento farmacológico , Depressão/psicologia , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Ácido Hidroxi-Indolacético/metabolismo , Masculino , Camundongos , Nortriptilina/farmacologia , Paroxetina/farmacologia , Serotonina/metabolismo , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Natação/psicologia
11.
Neurosci Lett ; 273(3): 175-8, 1999 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-10515187

RESUMO

The aim of this paper is to study the influence of salmon calcitonin (SCT) on opioid analgesia when opioid transduction pathways are functionally uncoupled from Gi/o proteins by treatment with pertussis toxin (PTX). The antinociceptive effect of morphine and three selective opioid agonists, [D-Ala2,N-Me-Phe2,Gly5-ol]enkephalin (DAMGO) (OP(3-mu receptor agonist), [D-Pen2.5]-enkephalin (OP-1-delta receptor agonist) and trans-( +/- )-3,4-dichloro-N-methyl-N-[2-1(-pyrrolidinyl)-cyclohexyl]-benzene-acetam ide methane sulfonate (U-50, 488H) (OP1-kappareceptor agonist) was evaluated, using the tail flick test, in mice treated with PTX or with PTX and SCT. PTX blocked the antinociceptive effect of the opioids, being the antinociception similar in control animals and in mice treated with PTX and SCT. Thus, SCT prevents the effect of the blockade of Gi/o-proteins. From this it could be suggested that calcitonin activates alternative antinociceptive mechanisms that are not dependent on Gi/o-proteins.


Assuntos
Analgesia , Analgésicos/farmacologia , Calcitonina/farmacologia , Proteínas de Ligação ao GTP/efeitos dos fármacos , Toxina Pertussis , Receptores Opioides/efeitos dos fármacos , Fatores de Virulência de Bordetella/antagonistas & inibidores , Analgésicos Opioides , Animais , Ala(2)-MePhe(4)-Gly(5)-Encefalina , Masculino , Camundongos , Morfina , Dor/tratamento farmacológico , Desacopladores/farmacologia
12.
Brain Res ; 845(2): 130-8, 1999 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-10536192

RESUMO

The analgesic effect of calcitonin when serotonin (5-HT) concentration is increased and the involvement of some 5-HT receptors were studied using the writhing test in mice. 5-hydroxytryptophan (5-HTP) administration increased both 5-HT levels in the central nervous system (CNS) and calcitonin analgesia. The 5-HT(1A) agonist (+/-)-8-hydroxy-2-dipropylaminotetralin hydrobromide (8-OH-DPAT) diminished calcitonin analgesia, this effect being antagonised by the 5-HT(1A) antagonist (WAY 100, 135). As the stimulation of 5-HT(1A) autoreceptors reduces the turnover of 5-HT, the effect of 8-OH-DPAT on calcitonin analgesia may be attributed to this decrease. The 5-HT(2A-2C) agonist (+/-)-1-(4-iodo-2,5-dimethoxyphenyl)-2-aminopropane hydrochloride (DOI) diminished calcitonin analgesia. A sub-analgesic dose of the 5-HT(2A) antagonist ketanserin failed to prevent this effect. The 5-HT(3) agonist (+/-)-2-methyl-5-hydroxytryptamine maleate (2-methyl-5-HT) potentiated calcitonin analgesia, whereas it was significantly reduced by the 5-HT(3) antagonist tropisetron. The effect of 2-methyl-5-HT on calcitonin analgesia was also reversed by tropisetron, This result suggests that the 5-HT(3) receptor may play an important role in the relationship between calcitonin and the serotonergic system. Tropisetron also reversed the analgesia induced by calcitonin plus 5-HTP corroborating importance of the 5-HT(3) receptors.


Assuntos
Analgésicos/farmacologia , Química Encefálica/efeitos dos fármacos , Calcitonina/farmacologia , Dor/fisiopatologia , Receptores de Serotonina/fisiologia , 8-Hidroxi-2-(di-n-propilamino)tetralina/farmacologia , Animais , Relação Dose-Resposta a Droga , Indóis/farmacologia , Indofenol/análogos & derivados , Indofenol/farmacologia , Ketanserina/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos , Nociceptores/efeitos dos fármacos , Nociceptores/fisiologia , Dor/tratamento farmacológico , Medição da Dor/métodos , Piperazinas/farmacologia , Piridinas/farmacologia , Receptores 5-HT3 de Serotonina , Serotonina/análogos & derivados , Serotonina/farmacologia , Antagonistas da Serotonina/farmacologia , Agonistas do Receptor de Serotonina/farmacologia , Tropizetrona
13.
Neurosci Lett ; 262(1): 25-8, 1999 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-10076864

RESUMO

The analgesic effect of three different opioid agonists, DAMGO ([D-Ala2,N-Me-Phe4,Gly5-ol]enkephalin), U-50,488H (trans-3,4-dichloro-N-methyl-N-[2-(1-pyrrolidynyl)cyclohexyl] benzene-aceramide methane sulphonate), and [D,Pen2-D,Pen5]-enkephalin, which act upon mu, delta and kappa opioid receptors, respectively, was compared in the presence and absence of salmon-calcitonin (s-CT). The analgesic test used was the writhing test in mice. The analgesic effect of the opioids was significantly enhanced by pretreatment of the animals with s-CT intraperitoneally (i.p.) administered. This effect was more evident for the delta and kappa-agonists. The present result suggests that the joint administration of s-CT and opioids may be a useful and interesting alternative in the treatment of painful diseases resistant to other treatments.


Assuntos
Analgésicos Opioides/farmacologia , Calcitonina/farmacologia , Receptores Opioides/agonistas , Receptores Opioides/metabolismo , (trans)-Isômero de 3,4-dicloro-N-metil-N-(2-(1-pirrolidinil)-ciclo-hexil)-benzenoacetamida/administração & dosagem , Analgésicos não Narcóticos/administração & dosagem , Analgésicos Opioides/administração & dosagem , Animais , Calcitonina/administração & dosagem , Ala(2)-MePhe(4)-Gly(5)-Encefalina , D-Penicilina (2,5)-Encefalina , Encefalinas/administração & dosagem , Injeções Intraperitoneais , Injeções Intraventriculares , Masculino , Camundongos , Receptores Opioides delta/agonistas , Receptores Opioides delta/metabolismo , Receptores Opioides kappa/agonistas , Receptores Opioides kappa/metabolismo , Receptores Opioides mu/agonistas , Receptores Opioides mu/metabolismo
14.
Gen Pharmacol ; 28(2): 331-6, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9013213

RESUMO

1. Pain threshold, behavioral parameters, and monoamine levels were compared in two groups of rats: adult (12 months old) and old rats (25 months old). 2. No differences in nociception were found between the two groups using the tail-shock test. 3. Behavioral experiments with the holeboard test showed that locomotor activity and exploration activity were lower in aged animals, whereas no significant differences were found in emotivity. 4. Using high-performance liquid chromatography (HPLC) techniques, we found that serotonin and dopamine showed lower levels in the old group.


Assuntos
Envelhecimento/fisiologia , Comportamento Animal/fisiologia , Dopamina/sangue , Limiar da Dor/fisiologia , Serotonina/sangue , Animais , Cromatografia Líquida de Alta Pressão , Dopamina/metabolismo , Masculino , Medição da Dor , Ratos , Ratos Wistar , Serotonina/metabolismo
15.
Eur J Pharmacol ; 340(1): 81-7, 1997 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-9527510

RESUMO

Calcitonin can selectively modulate the effects of opioids on the rat hypothalamic-pituitary-adrenal axis and increase the release of corticosterone induced by a kappa-opioid receptor agonist. Considerable evidence supports the involvement of opioid and serotonergic systems in the analgesic effect of calcitonin. In this study, the involvement of hypothalamic serotonergic pathways in the calcitonin potentiation of the effect of (trans-(+/-)-3,4-dichloro-N-methyl-N-[2-(1-pyrrolidinyl) cyclohexyl]-benzeneacetamide methane sulphonate (U-50,488H) on the secretion of corticosterone was examined. The correlation between the calcitonin-induced potentiation of the pituitary adrenal response to U-50,488H and changes in serotonin turnover was evaluated. Our results show that the increase in the release of corticosterone induced by treatment with calcitonin + U-50,488H was not evident when the turnover of serotonin was decreased by inhibition of its synthesis with m-hydroxybenzylhydrazine (NSD 1015) or by blockade of its metabolism with trans-2-phenylcyclopropylamine (tranylcypromine). Although other factors can not be discarded, from the present data it can be suggested that the serotonergic system plays an important role in the interaction calcitonin-kappa-opioid receptor agonist in the hypothalamic-pituitary-adrenal axis.


Assuntos
(trans)-Isômero de 3,4-dicloro-N-metil-N-(2-(1-pirrolidinil)-ciclo-hexil)-benzenoacetamida/farmacologia , Analgésicos não Narcóticos/farmacologia , Calcitonina/farmacologia , Corticosterona/metabolismo , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Receptores Opioides kappa/agonistas , Serotonina/metabolismo , 5-Hidroxitriptofano/metabolismo , Animais , Inibidores das Descarboxilases de Aminoácidos Aromáticos , Corticosterona/sangue , Inibidores Enzimáticos/farmacologia , Hidrazinas/farmacologia , Ácido Hidroxi-Indolacético/metabolismo , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Sistema Hipotálamo-Hipofisário/metabolismo , Masculino , Inibidores da Monoaminoxidase/farmacologia , Sistema Hipófise-Suprarrenal/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de Hormônios Reguladores de Hormônio Hipofisário/efeitos dos fármacos , Receptores de Hormônios Reguladores de Hormônio Hipofisário/metabolismo , Serotonina/sangue , Tranilcipromina/farmacologia
16.
Br J Pharmacol ; 119(5): 804-6, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8922724

RESUMO

1. In order to clarify one of the mechanisms involved in the analgesic effect of calcitonin, we have tested the in vitro modifications induced by calcitonin on the effect of opioids. 2. The inhibition of the contractions induced by opioids or clonidine, in guinea-pig ileum or in mouse vas deferens, were significantly reduced in tissues incubated with pertussis toxin (PTX). When tissues were incubated with PTX and calcitonin, the inhibitory effect was restored. 3. These results suggest that calcitonin is able to potentiate a non-PTX-sensitive mechanism of transduction and support the possibility of involvement of similar G-proteins in the effects of opioid and alpha 2-adrenoceptor agonists.


Assuntos
Calcitonina/metabolismo , Toxina Pertussis , Receptores Opioides/metabolismo , Fatores de Virulência de Bordetella/farmacologia , Agonistas de Receptores Adrenérgicos alfa 2 , Agonistas alfa-Adrenérgicos/metabolismo , Agonistas alfa-Adrenérgicos/farmacologia , Animais , Clonidina/metabolismo , Clonidina/farmacologia , Cobaias , Técnicas In Vitro , Masculino , Camundongos
17.
Psychopharmacology (Berl) ; 127(2): 123-32, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8888378

RESUMO

The effects of single and repeated (9 times) administration of two dihydropyridines (DHPs), nimodipine (NIM) and nifedipine (NIF) (5 mg/kg per 12 h and 2.5 mg/kg per 12 h, IP), on the behavior of male adult rats in the holeboard and in the plus-maze, were investigated. Besides, the effects of repeated administration of the drugs on the levels of dopamine (DA), serotonin (5-HT), and their respective major metabolites in several regions of the central nervous system (CNS) were also assessed. The effects of single and repeated administration of the drugs were similar. Both DHPs caused a significant decrease in general motor activity which was evident in both tests and more marked, with the higher doses. The two exploratory parameters measured in the holeboard, i.e. head-dipping frequency and duration, were dissociated under pharmacological treatment. The drug-treated animals did not show an increased emotionality in the holeboard. However, in the plus-maze, NIF (5 mg/kg) and to a lesser extent NIM, appeared to induce some anxiety-related responses which may be secondary, at least in part, to the depressing effect on activity and exploration. Repeated administration of NIM and NIF caused an increase in striatal DA and DOPAC levels, whilst no effects were found on serotonergic system in any of the regions of the CNS analyzed.


Assuntos
Comportamento Animal/efeitos dos fármacos , Química Encefálica/efeitos dos fármacos , Bloqueadores dos Canais de Cálcio/farmacologia , Dopamina/análise , Nifedipino/farmacologia , Nimodipina/farmacologia , Serotonina/análise , Ácido 3,4-Di-Hidroxifenilacético/análise , Animais , Relação Dose-Resposta a Droga , Ácido Homovanílico/análise , Ácido Hidroxi-Indolacético/análise , Masculino , Ratos , Ratos Wistar
18.
J Pharm Pharmacol ; 48(4): 433-6, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8794997

RESUMO

The aim of the present study was to analyse the contractility of the isolated vas deferens from hypercholesterolaemic rabbits; for this purpose we evaluated the contractile response induced by noradrenaline and by electrical stimulation. A significant increase in the amplitude of adrenergic and non-adrenergic responses was observed in vas deferens from hypercholesterolaemic rabbits. These data suggest an increase in the contractility of the smooth muscle in these animals.


Assuntos
Agonistas Adrenérgicos/farmacologia , Colesterol na Dieta/farmacologia , Músculo Liso/fisiologia , Norepinefrina/farmacologia , Receptores Opioides kappa/agonistas , Ducto Deferente/fisiologia , (trans)-Isômero de 3,4-dicloro-N-metil-N-(2-(1-pirrolidinil)-ciclo-hexil)-benzenoacetamida , Animais , Anti-Hipertensivos/farmacologia , Relação Dose-Resposta a Droga , Estimulação Elétrica , Hipercolesterolemia/fisiopatologia , Masculino , Contração Muscular/efeitos dos fármacos , Contração Muscular/fisiologia , Músculo Liso/efeitos dos fármacos , Pirrolidinas/farmacologia , Coelhos , Ducto Deferente/efeitos dos fármacos
19.
Gen Pharmacol ; 26(8): 1695-9, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8745158

RESUMO

1. The interaction of intraperitoneal administration of salmon-calcitonin with opioids was studied. The study was carried out using guinea pig ileum (mu and kappa-opioid receptors), rabbit vas deferens (kappa-opioid receptors) and mouse vas deferens (delta-opioid receptors), and selective mu, delta and kappa agonists were used in the pertinent tissues. 2. The treatment with salmon-calcitonin increased, in a dose-dependent manner, the effect of U-50,488H in guinea pig ileum and rabbit vas deferens and the effects of [D-Pen2, D-Pen5] enkephalin in mouse vas deferens. 3. The treatment with analgesic doses of salmon-calcitonin enhances the in vitro effects of kappa- and delta-opioid agonists. The increase of the effectiveness of the opioid agonists may be one of the mechanisms involved on the analgesia induced by salmon-calcitonin.


Assuntos
Analgésicos/farmacologia , Calcitonina/farmacologia , Entorpecentes/farmacologia , (trans)-Isômero de 3,4-dicloro-N-metil-N-(2-(1-pirrolidinil)-ciclo-hexil)-benzenoacetamida , Animais , Relação Dose-Resposta a Droga , Ala(2)-MePhe(4)-Gly(5)-Encefalina , Encefalinas/farmacologia , Cobaias , Íleo/efeitos dos fármacos , Íleo/fisiologia , Técnicas In Vitro , Masculino , Camundongos , Contração Muscular/efeitos dos fármacos , Pirrolidinas/farmacologia , Coelhos , Receptores Opioides delta/efeitos dos fármacos , Receptores Opioides kappa/efeitos dos fármacos , Ducto Deferente/efeitos dos fármacos , Ducto Deferente/fisiologia
20.
Gen Pharmacol ; 26(3): 641-7, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-7789740

RESUMO

1. When the analgesic effect of salmon-calcitonin (S-CT) and of eel-calcitonin (E-CT), as well as their influence on the morphine-analgesia were compared, no significant differences were found. 2. While on isolated tissues, E-CT induced a significant increase on the effect of bremazocine, [D-Pen2,D-Pen5]enkephalin and [Met5]enkephalin and no changes were observed on the effect of DAMGO, suggesting that E-CT increases the effects of opioids acting on delta or kappa receptors but not on mu receptors. 3. These findings corroborate the possibility of interactions between calcitonin and the opioid system.


Assuntos
Analgésicos/farmacologia , Calcitonina/farmacologia , Entorpecentes/farmacologia , Animais , Benzomorfanos/farmacologia , Relação Dose-Resposta a Droga , Interações Medicamentosas , Ala(2)-MePhe(4)-Gly(5)-Encefalina , D-Penicilina (2,5)-Encefalina , Encefalinas/farmacologia , Cobaias , Técnicas In Vitro , Masculino , Camundongos , Morfina/farmacologia , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Medição da Dor/efeitos dos fármacos , Limiar da Dor/efeitos dos fármacos , Coelhos , Ratos , Ratos Wistar
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...