Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 29
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Eur J Obstet Gynecol Reprod Biol ; 299: 22-25, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38823309

RESUMO

Agenesis of inferior vena cava (AIVC) is an extremely rare congenital abnormality. In AIVC, venous flow from the lower extremities enter superior vena cava mainly through the azygous and hemiazygous system, forming anastomotic collateral vessels. A global increase in intra-abdominal pressure by the gravid uterus may further stress the collateral system, increase venous stasis and decrease venous return. We present the management of a 37-year old pregnant woman with AIVC who underwent caesarean section with norepinephrine infusion and general anaesthesia. She presented with shortness of breath when seated, episodes of dizziness while walking or sitting upright with subsequent tachycardia. Cardiac status was monitored using an arterial pulse contour CO monitor. We did not observe large fluctuations in CO, SV, MAP during induction and intubation as well as during delivery. We believe that administration of an infusion of norepinephrine from induction to anaesthesia through caesarean section contributed to this result. Sympathetic activation caused venoconstriction, which significantly increased venous return and maintained haemodynamic stability.


Assuntos
Cesárea , Veia Cava Inferior , Humanos , Feminino , Gravidez , Veia Cava Inferior/anormalidades , Adulto , Complicações Cardiovasculares na Gravidez , Norepinefrina/administração & dosagem , Norepinefrina/uso terapêutico
2.
Sci Rep ; 12(1): 5301, 2022 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-35351938

RESUMO

Meagre (Argyrosomus regius), is a benthopelagic species rapidly emerging in aquaculture, due to its low food to biomass conversion rate, good fillet yield and ease of production. Tracing a species genomic background along with describing the genetic basis of important traits can greatly influence both conservation strategies and production perspectives. In this study, we employed ddRAD sequencing of 266 fish from six F1 meagre families, to construct a high-density genetic map comprising 4529 polymorphic SNP markers. The QTL mapping analysis provided a genomic appreciation for the weight trait identifying a statistically significant QTL on linkage group 15 (LG15). The comparative genomics analysis with six teleost species revealed an evolutionarily conserved karyotype structure. The synteny observed, verified the already well-known fusion events of the three-spine stickleback genome, reinforced the evidence of reduced evolutionary distance of Sciaenids with the Sparidae family, reflected the evolutionary proximity with Dicentrarchus labrax, traced several putative chromosomal rearrangements and a prominent putative fusion event in meagre's LG17. This study presents novel elements concerning the genome evolutionary history of a non-model teleost species recently adopted in aquaculture, starts to unravel the genetic basis of the species growth-related traits, and provides a high-density genetic map as a tool that can help to further establish meagre as a valuable resource for research and production.


Assuntos
Bass , Genoma , Animais , Bass/genética , Evolução Biológica , Mapeamento Cromossômico , Ligação Genética , Genoma/genética , Humanos
3.
Mar Biotechnol (NY) ; 20(5): 611-622, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29948235

RESUMO

The present study identified and characterized six key genes involved in the hypothalamic-pituitary-interrenal (HPI) axis of gilthead sea bream (Sparus aurata), a commercially important European aquaculture species. The key genes involved in the HPI axis for which gene structure and synteny analysis was carried out, comprised of two functional forms of glucocorticoid receptors (GR), as well as three forms of pro-opiomelanocortin (POMC) genes and one form of mineralocorticoid receptor (MR) gene. To explore their functional roles during development but also in the stress response, the expression profiles of gr1, gr2, mr, pomc_aI, pomc_aII, and pomc_ß were examined during early ontogeny and after an acute stress challenge. The acute stress challenge was applied at the stage of full formation of all fins, where whole body cortisol was also measured. Both the cortisol and the molecular data implied that sea bream larvae at the stage of the full formation of all fins at 45 dph are capable of a response to stress of a similar profile as observed in adult fish.


Assuntos
Hidrocortisona/metabolismo , Dourada/metabolismo , Animais , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/metabolismo , Receptores de Mineralocorticoides/genética , Receptores de Mineralocorticoides/metabolismo , Dourada/genética , Dourada/fisiologia , Estresse Fisiológico/genética , Estresse Fisiológico/fisiologia
4.
Sci Rep ; 8(1): 3564, 2018 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-29476120

RESUMO

Sex differentiation is a puzzling problem in fish due to the variety of reproductive systems and the flexibility of their sex determination mechanisms. The Sparidae, a teleost family, reflects this remarkable diversity of sexual mechanisms found in fish. Our aim was to capture the transcriptomic signature of different sexes in two protogynous hermaphrodite sparids, the common pandora Pagellus erythrinus and the red porgy Pagrus pagrus in order to shed light on the molecular network contributing to either the female or the male phenotype in these organisms. Through RNA sequencing, we investigated sex-specific differences in gene expression in both species' brains and gonads. The analysis revealed common male and female specific genes/pathways between these protogynous fish. Whereas limited sex differences found in the brain indicate a sexually plastic tissue, in contrast, the great amount of sex-biased genes observed in gonads reflects the functional divergence of the transformed tissue to either its male or female character. Α common "crew" of well-known molecular players is acting to preserve either sex identity of the gonad in these fish. Lastly, this study lays the ground for a deeper understanding of the complex process of sex differentiation in two species with an evolutionary significant reproductive system.


Assuntos
Perciformes/genética , Processos de Determinação Sexual/genética , Diferenciação Sexual/genética , Transcriptoma/genética , Animais , Feminino , Regulação da Expressão Gênica no Desenvolvimento/genética , Gônadas/crescimento & desenvolvimento , Organismos Hermafroditas/genética , Organismos Hermafroditas/crescimento & desenvolvimento , Sequenciamento de Nucleotídeos em Larga Escala , Masculino , Perciformes/crescimento & desenvolvimento , Análise para Determinação do Sexo
5.
Sci Rep ; 7: 46075, 2017 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-28378841

RESUMO

Temporal patterns of whole-body α-MSH concentrations and of transcripts of melanocortin receptors during early development as well as the endocrine response (α-MSH, cortisol, MCR mRNAs) to stress at the end of the larval period were characterized in Dicentrarchus labrax. Immunohistochemistry showed α-MSH positive cells in the pituitary pars intermedia in all stages examined. As development proceeds, α-MSH content gradually increases; mRNA levels of mc2r and mc4r remain low until first feeding where peak values are observed. Mc1r expression was constant during development, pomc mRNA levels remain low until the stage of flexion after which a significant increase is observed. At the stage of the formation of all fins, whole-body cortisol and α-MSH concentrations responded with peak values at 2 h post stress. Additionally, the stress challenge resulted in elevated transcript levels of pomc, mc2r and mc4r but not in mc1r, with a pattern characterized by peak values at 1 h post stress and a strong correlation with whole body α-MSH concentrations was found. Our data provide for the first time a view on the importance of the α-MSH stress response in early development of European sea bass, an additional and relatively poorly understood signal involved in the stress response in teleosts.


Assuntos
Bass/metabolismo , Receptores de Melanocortina/metabolismo , alfa-MSH/metabolismo , Animais , Bass/genética , Regulação da Expressão Gênica , Hidrocortisona/metabolismo , Larva/metabolismo , Pró-Opiomelanocortina/genética , Pró-Opiomelanocortina/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Radioimunoensaio , Receptores de Melanocortina/genética , Estresse Fisiológico , Fatores de Tempo
6.
Behav Brain Res ; 317: 109-121, 2017 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-27638037

RESUMO

Early life adversity may be critical for the brain structural plasticity that in turn would influence juvenile behaviour. To address this, we questioned whether early life environment has an impact on stress responses latter in life, using European sea bass, Dicentrarchus labrax, as a model organism. Unpredictable chronic low intensity stress (UCLIS), using a variety of moderate intensity stressors, was applied during two early ontogenetic stages, flexion or formation all fins. At juvenile stage, fish were exposed to acute stress and plasma cortisol, brain mRNA expression of corticosteroid receptors' genes (gr1, gr2, mr) and brain cell proliferation (using BrdU immunohistochemistry) were determined in experimental and matched controls. UCLIS treatment specifically decreased brain gr1 expression in juveniles, but had no effect on the juvenile brain cell proliferation pattern within the major neurogenic zones studied of dorsal (Dm, Dld) and ventral (Vv) telencephalic, preoptic (NPO) areas, periventricular tectum gray zone (PGZ) and valvula cerebellum (VCe). In contrast, exposure to acute stress induced significant plasma cortisol rise, decreases of cerebral cell proliferation in juveniles, not previously exposed to UCLIS, but no effect detected on the expression levels of gr1, gr2 and mr in all groups of different early life history. Interestingly, juveniles with UCLIS history showed modified responses to acute stress, attenuating acute stress-induced cell proliferation decreases, indicating a long-lasting effect of early life treatment. Taken together, early life mild stress experience influences an acute stress plasticity end-point, cerebral cell proliferation, independently of the stress-axis activation, possibly leading to more effective coping styles.


Assuntos
Encéfalo/crescimento & desenvolvimento , Encéfalo/patologia , Proliferação de Células/fisiologia , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Receptores de Esteroides/metabolismo , Estresse Psicológico/patologia , Análise de Variância , Animais , Bass , Bromodesoxiuridina/metabolismo , Proteínas de Ligação a Ácido Graxo/metabolismo , Hidrocortisona/sangue , Proteínas do Tecido Nervoso/metabolismo , RNA Mensageiro/metabolismo , Receptores de Esteroides/genética
7.
Sci Rep ; 6: 34858, 2016 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-27703277

RESUMO

Understanding the stress responses of organisms is of importance in the performance and welfare of farmed animals, including fish. Especially fish in aquaculture commonly face stressors, and better knowledge of their responses may assist in proper husbandry and selection of breeding stocks. European sea bass (Dicentrarchus labrax), a species with high cortisol concentrations, is of major importance in this respect. The main objectives of the present study were to assess the repeatability and consistency of cortisol stress response and to identify differences in liver transcription profiles of European sea bass individuals, showing a consistent low (LR) or high (HR) cortisol response. The progeny of six full sib families was used, and sampled for plasma cortisol after an acute stress challenge once per month, for four consecutive months. Results suggest that cortisol responsiveness was a repeatable trait with LR and HR fish showing low or high resting, free and post-stress cortisol concentrations respectively. Finally, the liver transcription profiles of LR and HR fish showed some important differences, indicating differential hepatic regulation between these divergent phenotypes. These transcription differences were related to various metabolic and immunological processes, with 169 transcripts being transcribed exclusively in LR fish and 161 exclusively in HR fish.


Assuntos
Bass/sangue , Proteínas de Peixes/genética , Perfilação da Expressão Gênica/métodos , Hidrocortisona/sangue , Animais , Aquicultura , Bass/genética , Regulação da Expressão Gênica , Redes Reguladoras de Genes , Fígado/metabolismo , Estresse Fisiológico
8.
BMC Genomics ; 17: 506, 2016 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-27461489

RESUMO

BACKGROUND: Teleosts are exposed to a broad range of external stimuli, which may be either of acute or chronic nature. The larval phase of certain fish species offer a unique opportunity to study the interactions between genes and environmental factors during early life. The present study investigates the effects of early-life events, applied at different time points of early ontogeny (first feeding, flexion and development of all fins; Phase 1) as well as on the subsequent juvenile stage after the application of an additional acute stressor (Phase 2) in the gilthead sea bream (Sparus aurata), a commercially important European aquaculture species. Animal performance, the cortisol response and gene expression patterns during early development as well as on the subsequent phases (juveniles) after the application of additional acute stressors were investigated. RESULTS: Significant differences on fish performance were found only for juveniles exposed to early-life events at the phase of the formation of all fins. On the transcriptome level distinct expression patterns were obtained for larvae as well as for juveniles with the most divergent expression pattern found to be again at the phase of the development of all fins, which showed to have also an impact later on in the acute stress response of juveniles. CONCLUSIONS: The present study showed that applying an early-life protocol, characterized by the unpredictable, variable and moderate intensity of the applied stimuli provides a relative realistic model to evaluate the impact of daily aquaculture practices on fish performance. In addition, the power of investigating global gene expression patterns is shown, providing significant insights regarding the response of early-life events during development and as juveniles after the application of extra acute stressors.


Assuntos
Dourada/genética , Transcriptoma , Animais , Análise por Conglomerados , Biologia Computacional/métodos , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Hidrocortisona/biossíntese , Estágios do Ciclo de Vida , Anotação de Sequência Molecular , Dourada/crescimento & desenvolvimento , Dourada/metabolismo , Estresse Fisiológico/genética
9.
J Fish Biol ; 86(4): 1271-85, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25846855

RESUMO

The effects of different tank volumes (2000, 500 and 40 l) on European sea bass Dicentrarchus labrax larval rearing, relating to growth, survival, quality and stress variables, were investigated. A dynamic energy budget (DEB) model was used to analyse the results. The hydrodynamics of the tanks exhibited differences, with the water currents in the 2000 l tanks to be almost one order of magnitude stronger than those in the 40 l ones. Important differences in fish growth were observed between small and large tank-rearing volumes, with the smallest tank resulting in the slowest growth. Based on the DEB model analysis, growth differences were related to feeding rates, with growth in the smaller tank limited by food availability. Differences in survival rates were not statistically significant among the tank-rearing volumes. The quality evaluation of the fry (in terms of swimbladder, jaw and skeletal abnormalities) showed differences, with the smallest tank having the highest percentage of deformed individuals. This could be attributed to both the feeding variances and the hydrodynamics in the tanks. No differences were observed in terms of whole-body cortisol at the two developmental stages; flexion, and when the larvae body was fully covered by melanophores; when analysis was performed. This indicates that the allostatic load exerted on fish of different groups was similar and inside the fish-coping abilities range, in terms of the cortisol response axis. The selection of the experimental scale is of importance, especially when the results are to be transferred and applied on an industrial scale.


Assuntos
Aquicultura/métodos , Bass/fisiologia , Meio Ambiente , Animais , Hidrocortisona/química , Hidrodinâmica , Larva/crescimento & desenvolvimento , Modelos Biológicos , Estresse Fisiológico , Movimentos da Água
10.
Ophthalmologe ; 111(9): 882-6, 2014 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-25204530

RESUMO

OBJECTIVE OF SURGERY: The aim of the surgical treatment of retinal detachment is retinal reattachment especially of the central portion for the best possible regeneration of functional visual outcome. INDICATIONS: Total and subtotal retinal detachments in combination with macular involvement were investigated. SURGICAL TECHNIQUE: After complete 20 or 23-gauge pars plana vitrectomy (ppV) the internal limiting membrane (ILM) was stained with Brilliant Blue for 30 s. The detached and more mobile central retina was weighted and stabilized with decaline so that the raised ILM could be carefully peeled away under the decaline level. Removal of residual decaline was followed by drainage of subretinal fluids through the retinal foramen and fluid-air exchange. To prevent renewed detachment circular laser coagulation was performed under air and followed by tamponade with silicone oil or SF6 gas depending on the status of the retina. RESULTS: The surgical intervention could be successfully performed in all selected patients with a primary reattachment rate of 100 %. In the 12-month follow-up period no renewed detachment or formation of a secondary epiretinal membrane was observed. The postoperative visual acuity (VA) showed a statistically significant increase (p < 0.0001) in the Wilcoxon test for paired samples. CONCLUSION: Primary vitrectomy with ILM peeling under decaline is a promising but ambitious surgical intervention for the treatment of incomplete and complete retinal detachment with and without proliferative vitreoretinopathy.


Assuntos
Membrana Epirretiniana/cirurgia , Naftalenos/uso terapêutico , Descolamento Retiniano/patologia , Descolamento Retiniano/cirurgia , Vitrectomia/métodos , Idoso , Terapia Combinada , Feminino , Humanos , Masculino , Resultado do Tratamento
11.
Sci Rep ; 4: 5525, 2014 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-24984570

RESUMO

The cortisol stress response and the molecular programming of the corticoid axis were characterized for the first time during early ontogeny in a Mediterranean marine teleost, the European sea bass (Dicentrarchus labrax). Sea bass embryos, pre-larvae and larvae at specific points of development were exposed to acute stressors and the temporal patterns of cortisol whole body concentrations and the expression of genes involved in corticosteroid biosynthesis, degradation and signaling were determined. Expression of genes (gr1, gr2, mr, crf) involved into the corticoid response regulation combined with histological data indicated that, although a cortisol stress response is evident for the first time around first feeding, a pattern becomes established in larvae at flexion until the formation of all fins. Moreover, mRNA transcript levels of 11ß-hydroxylase and 11ß-hsd2 showed a strong correlation with the whole body cortisol concentrations. Concluding, our data reveal the presence of an adaptive mechanism in European sea bass at early ontogeny enabling to cope with external stressful stimuli and provide a better insight into the onset and regulation of the stress response in this species.


Assuntos
Bass/fisiologia , Hidrocortisona/farmacologia , Sistema Hipotálamo-Hipofisário/embriologia , Sistema Hipotálamo-Hipofisário/fisiologia , Rim/fisiologia , Estresse Fisiológico/fisiologia , Animais , Bass/embriologia , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Rim/efeitos dos fármacos , Rim/embriologia , Estresse Fisiológico/efeitos dos fármacos
12.
Fish Physiol Biochem ; 40(3): 911-9, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24343759

RESUMO

European sea bass (Dicentrarchus labrax), one of the most economically important fish in Mediterranean mariculture, shows high basal cortisol concentrations compared with other teleosts. The present study aims (a) to identify cortisol diel variation in fish held under a 12L:12D cycle and minimum handling stress, and (b) to establish the effect of fish size and stressor duration on the cortisol response. The results indicate high intrapopulation variability in plasma cortisol and a significant diel fluctuation with a peak value at dusk (18 h). Stressors of different intensity and/or duration affected the cortisol stress response in a differential manner according to fish size (and/or age). Maximum cortisol values in small-size fish were found at 1 and 2 h post-stress, depending on the duration of the stressor, while at 0.5 h post-stress in large fish regardless stress duration.


Assuntos
Bass/sangue , Ritmo Circadiano , Hidrocortisona/sangue , Estresse Psicológico/sangue , Animais , Tamanho Corporal , Aglomeração , Distribuição Aleatória , Fatores de Tempo
13.
Gen Comp Endocrinol ; 173(2): 313-22, 2011 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-21712040

RESUMO

The aim of the present study was to examine the species-specific stress response for seven Mediterranean fishes in culture. Also, to evaluate the method of measuring free cortisol concentration in the rearing water as a non-invasive and reliable indicator of stress in marine species, of aquaculture importance. Gilthead sea bream, Sparus aurata (Sparidae); common dentex, Dentex dentex (Sparidae); common Pandora, Pagellus erythrinus (Sparidae); sharpsnout sea bream, Diplodus puntazzo (Sparidae); dusky grouper, Epinephelus marginatus (Serranidae); meagre, Argyrosomus regius (Sciaenidae) and European sea bass, Dicentrarchus labrax (Moronidae) were subjected to identical acute stress (5-6 min chasing and 1-1.5 min air exposure) under the same environmental conditions and samples were analyzed by the same procedures. Results indicated that there was a clear species-specificity in the magnitude, timing and duration of the stress response in terms of cortisol, glucose and lactate. European sea bass showed a very high response and dusky grouper and meagre a very low response, except plasma glucose concentrations of dusky grouper which was constantly high, while sharpsnout sea bream presented a protracted stress response, up to 8h. The present study confirmed that free cortisol release rate into the water can be used as a reliable stress indicator.


Assuntos
Peixes/metabolismo , Estresse Fisiológico/fisiologia , Animais , Glicemia/análise , Peixes/fisiologia , Hidrocortisona/sangue , Ácido Láctico/sangue , Mar Mediterrâneo , Perciformes/metabolismo , Perciformes/fisiologia , Dourada/metabolismo , Dourada/fisiologia , Especificidade da Espécie
14.
Klin Monbl Augenheilkd ; 227(1): 43-6, 2010 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-20091449

RESUMO

BACKGROUND: Irrigation of the lacrimal duct with silicone tube intubation, endoscopic microdrill dacryoplasty and external dacryocystorhinostomy (DCR) are commonly used in lacrimal duct surgery. Dacryocystography (DCG) is one of the standard procedures in preoperative imaging. This study evaluates the influence of individual parameters and the prognostic meaning of preoperative DCG on the success rates after lacrimal duct surgery, in order to predict more precisely the long-term outcome after different operative paradigms. MATERIALS AND METHODS: 145 patients (mean age 60 years; 32 % male) with lacrimal stenosis, who underwent lacrimal duct surgery in the University Eye Hospital Münster during 2002 were included in this retrospective study. Individual parameters (age, gender, preoperative duration of symptoms, lacrimal sac area and operative procedures) were recorded. The lacrimal sac area of each patient was calculated from preoperative DCG imaging. The individual parameters and the prognostic relevance of preoperative DCG were statistically analysed with regards to the long-term success rate after different surgical procedures. Criteria for success were an asymptomatic patient and a successful probing and irrigation of the lacrimal duct system at follow-up at 24 to 36 months after lacrimal duct surgery. RESULTS: With a mean success rate of 79 %, DCR was most effective regarding long-term outcome. Particularly in elderly patients DCG was superior to minimal-invasive procedures. The mean area of the lacrimal sac, calculated from DCG imaging, was 18 mm (2). There was a significant correlation (p = 0.001) between the area of the lacrimal sac and long-term success of DCR. CONCLUSION: Endoscopic microdrill dacryoplasty and DCR have the most successful options in the treatment of lacrimal stenosis. DCG was the most effective procedure in elderly patients. An enlargred lacrimal sac proved to be a positive prognostic factor for the long-term success of DCR.


Assuntos
Dacriocistorinostomia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Endoscopia , Feminino , Seguimentos , Humanos , Obstrução dos Ductos Lacrimais/diagnóstico por imagem , Masculino , Microcirurgia/métodos , Pessoa de Meia-Idade , Ducto Nasolacrimal/diagnóstico por imagem , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Prognóstico , Radiografia , Reoperação , Irrigação Terapêutica , Adulto Jovem
15.
Eur J Neurosci ; 24(9): 2631-42, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17100851

RESUMO

One-trial passive avoidance learning (PAL), where the aversive stimulus is the bitter-tasting substance methylanthranilate (MeA), affects neuronal and synaptic plasticity in learning-related areas of day-old domestic chicks (Gallus domesticus). Here, cell proliferation was examined in the chick forebrain by using 5-bromo-2-deoxyuridine (BrdU) at 24 h and 9 days after PAL. At 24 h post-BrdU injection, there was a significant reduction in labelling in MeA-trained chicks in both the dorsal hippocampus and area parahippocampalis, in comparison to controls. Moreover, double-immunofluorescence labelling for BrdU and the nuclear neuronal marker (NeuN) showed a reduction of neuronal cells in the dorsal hippocampus of the MeA-trained group compared with controls (35 and 49%, respectively). There was no difference in BrdU labelling in hippocampal regions between trained and control groups of chicks at 9 days post-BrdU injection; however, the number of BrdU-labelled cells was considerably lower than at 24 h post-BrdU injection, possibly due to migration of cells within the telencephalon rather than cell loss as apoptotic analyses at 24 h and 9 days post-BrdU injection did not demonstrate differences in cell death between treatment groups. Cortisol levels increased in the chick hippocampus of MeA-trained birds 20 min after PAL, suggesting the possibility of a stress-related mechanism of cell proliferation reduction in the hippocampus. In contrast to hippocampal areas, the olfactory bulb, an area strongly stimulated by the strong-smelling MeA, showed increased cell genesis in comparison to controls at both 24 h and 9 days post-training.


Assuntos
Aprendizagem da Esquiva/fisiologia , Proliferação de Células , Hipocampo/fisiologia , Plasticidade Neuronal/fisiologia , Animais , Animais Recém-Nascidos , Antígenos Nucleares/metabolismo , Apoptose/fisiologia , Bromodesoxiuridina/metabolismo , Galinhas , Imuno-Histoquímica , Proteínas do Tecido Nervoso/metabolismo
16.
Gen Comp Endocrinol ; 145(3): 247-53, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16253249

RESUMO

The skin colour of red porgy, Pagrus pagrus, can be modified by exposure to different background colours. Red and white background colours brighten the dark skin colour that develops under common culture conditions in red porgy. To assess whether skin colour is also modified by aquaculture related handling stress, we subjected red porgy to 5 min of netting stress combined with air exposure. Fish kept on a white background have: (1) a lighter skin colour, which is not influenced by an acute stressor, (2) a less saturated red colour, which significantly decreases 24h post-handling, and (3) a similar hue as fish kept on a red background. The first plasma parameters to rise after application of the stressor are cortisol, lactate and Na(+); then, glucose levels rose. Other plasma ions (Ca(2+), Cl(-), K(+)) were not affected up to 2h post-stressor, but had decreased at 8 and 24h after handling. Plasma pH decreased over the first 2h post-handling, indicative of plasma acidosis upon air exposure. The acidosis then coincided with increases in plasma lactate levels. As alphaMSH levels were not significantly affected by the stressor while cortisol levels showed a five to tenfold increase, we suggest that following acute stress in red porgy, plasma cortisol release is controlled by ACTH, perhaps in combination with a sympathic stimulation.


Assuntos
Adaptação Biológica/fisiologia , Perciformes/fisiologia , Pigmentação da Pele/fisiologia , Estresse Fisiológico/fisiopatologia , Animais , Glicemia/metabolismo , Cálcio/sangue , Cloretos/sangue , Cor , Hidrocortisona/sangue , Concentração de Íons de Hidrogênio , Ácido Láctico/sangue , Potássio/sangue , Sódio/sangue , Estresse Fisiológico/sangue , alfa-MSH/sangue
17.
Gen Comp Endocrinol ; 142(1-2): 186-92, 2005 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-15862562

RESUMO

The aim of the study was to elucidate the pattern of changes in the whole body concentrations of thyroid hormones (TH) and cortisol in eggs, pre-larvae, and larvae in the gilthead sea bream, Sparus aurata. The ontogeny of these hormones was related to specific morphological characteristics that characterize early development. TH and cortisol were detected in substantial amounts in the eggs of sea bream. T3 concentration in eggs was found to be higher than that of T4 (T3, 4.02+/-0.38 ng g-1; T4, 1.63+/-0.28 ng g-1), as it is often observed in marine teleosts. T4 decreased until hatching (T4, 1.01+/-0.58 ng g-1), while T3 reached a minimum at the time of first feeding (T3, 0.19+/-0.02 ng g-1). As development proceeded, both hormones displayed a similar pattern of changes with increasing concentrations until the completion of metamorphosis (T3, 15.84+/-2.92 ng g-1; T4, 9.78+/-2.39 ng g-1), indicating that the hypothalamo-adenohypophysial-thyroid axis begins to function soon after first feeding. The pattern of changes of cortisol (F) concentration was almost parallel to that of T4, starting from 0.83 ng g-1 in eggs. Minimum F concentration was observed at hatching (0.39+/-0.03 ng g-1) and maximum at melanophores and scale formation (14.82+/-2.71 and 14.82+/-3.12 ng g-1, respectively). Results provide data for the first time on the ontogeny of thyroid hormones and cortisol during the early development in sea bream and are in agreement with results in other fish species for an important action of TH during early development.


Assuntos
Envelhecimento/metabolismo , Hidrocortisona/metabolismo , Perciformes/crescimento & desenvolvimento , Perciformes/metabolismo , Hormônios Tireóideos/metabolismo , Animais , Embrião não Mamífero/metabolismo , Sistema Hipotálamo-Hipofisário/crescimento & desenvolvimento , Sistema Hipotálamo-Hipofisário/metabolismo , Larva/crescimento & desenvolvimento , Larva/metabolismo , Melanóforos/metabolismo , Óvulo/crescimento & desenvolvimento , Óvulo/metabolismo , Glândula Tireoide/crescimento & desenvolvimento , Glândula Tireoide/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...