18 research outputs found
Ultimobranchial gland of freshwater catfish, Heteropneustes fossilis, in response to calcitonin administration
Effects of ultimobranchialectomy (UBX) upon the bone catabolism and anabolism and on some aspects of the calcium metabolism regulation inAnguilla anguilla L.
Fluid Regulation and Physiological Adjustments in the Winter Skate, Leucoraja ocellata, Following Exposure to Reduced Environmental Salinities
Simultaneous modifications of ventilation and arterialP O2 by catecholamines in the eel,Anguilla anguilla L.: Participation of ? and ? effects
Effects of catecholamines on isolated systemic and branchial vascular beds of the cod,Gadus morhua
Pituitary response to environmental osmotic changes in the larval guppy, Lebistes reticulatus (Peters)
The exchangeable ionic space, and salinity effects upon ion, water, and urea turnover rates in the dogfish Poroderma africanum
Characterization of gluconeogenesis in hepatocytes isolated from the American eel,Anguilla rostrata LeSueur,
The significance of cortisol on acclimation to salinity in pejerrey Odontesthes bonariensis Importância do cortisol na aclimatação a salinidade em peixe-rei Odontesthes bonariensis
The role of cortisol on the osmoregulation of pejerrey Odontesthes bonariensis at different salinities was investigated in adult fish injected with 0.7mg hydrocortisone per 100g body weight of fish, and transferred to 0, 5 and 20ppt of NaCl. Blood cortisol was 566ng/ml at the beginning of the experiment (0h) but surged to 1250ng/ml within 3h in cortisol-injected fish. Cortisol levels were influenced not only by treatment but also by time, being higher at 3h compared to 24h. Salinity level, time of exposure and their interaction, but not cortisol treatment, significantly affected plasma osmolality and the concentration of ions Cl- and Na+. This study showed that exogenous cortisol does not seem to play a significant role on the regulation of plasma osmolality and concentration of individual ions in pejerrey.<br>Investigou-se a participação do cortisol na osmoregulação de peixe-rei Odontesthes bonariensis, em diferentes salinidades, em peixes adultos injetados com 0,7mg hidrocortisona por 100g de peso corporal, e transferidos para 0, 5 e 20ppt de NaCl. No inicio do experimento (0h), o cortisol encontrado no plasma foi de 566ng/ml, aumentando para 1250ng/ml em 3h em peixes injetados com cortisol. A concentração de cortisol foi influenciada não somente pelo tratamento, mas também pelo tempo, sendo maior 3h após a inoculação, comparada à 24h. A salinidade, o tempo de exposição e a interação desses dois fatores, mas não o tratamento com o cortisol, afetaram significativamente a osmolaridade e a concentração dos íons Cl- e Na+ do plasma. Este estudo mostrou que, o cortisol exógeno não influi significativamente na regulação da osmolaridade e da concentração de íons Na+ e Cl- no plasma em peixe-rei