Naltrexone Stimulates Lh Secretion in Vitro from the Common Carp (cyprinus Carpio L.) Pituitary Gland
نویسندگان
چکیده
The effects of naltrexone on the in vitro luteinizing hormone (LH) secretion from whole pituitary glands as well as from dispersed pituitary cells of common carp (Cyprinus carpio L.) in primary cell culture were studied. The perifusion of whole pituitary glands with naltrexone at a concentration of 10 M caused a significant increase of LH secretion compared to the control. This finding suggests that opioid peptides can indirectly affect LH secretion at the pituitary level, probably through the nerve terminals containing GnRH and/or DA present in the pituitary. In the perifusion of dispersed pituitary cells with naltrexone at concentrations of 10 or 10 M, significant increases of LH levels were found. Similar results were observed in static culture of dispersed carp pituitary cells: after 4 or 24 hours of culture in the medium containing naltrexone at concentrations of 10, 10 or 10 M, a dose-dependent, statistically significant increase of LH secretion to the culture medium was found. The results from dispersed pituitary cell perifusions or cell culture with naltrexone indicate that this antagonist directly affects the pituitary cells and stimulates LH release from carp gonadotrophs.
منابع مشابه
Steroid effects on the in vitro LH secretion from pituitary cells of sexually immature carp (Cyprinus carpio L.) under the influence of naltrexone and morphine
Dispersed cells from sexually immature carp (footlings) pituitaries were exposed to estradiol (E2) or testosterone (T) (both at 3 × 10 –8 M) in the presence of opioid receptor antagonist naltrexone (10–8 or 10–6 M) and/or agonist – morphine (10–8 or 10–6 M). Naltrexone alone at 10–6 M increased the LH level as compared with the control. Morphine (10–8 or 10–6 M), T and E2 had no influence on LH...
متن کاملA Comparative study of synthetic carp GnRH and carp pituitary homogenate effects on in vitro steroidogenesis of oocytes in common carp (Cyprinus carpio)
Vitellogenic stage carp ovaries were collected aseptically and the cells of ovarian follicles were dispersed by trypsin treatment and cultivated as monolayer. Control cultures were grown in medium M199 alone. Media for experimental cultures were supplemented either with 100 µl ml-1 of CPH and CPS-carp GnRH (cultivated pituitary cell secretion affected by 10-6, 10-8, 10-10 M carp GnRH). The dire...
متن کاملA Comparative study of synthetic carp GnRH and carp pituitary homogenate effects on in vitro steroidogenesis of oocytes in common carp (Cyprinus carpio)
Vitellogenic stage carp ovaries were collected aseptically and the cells of ovarian follicles were dispersed by trypsin treatment and cultivated as monolayer. Control cultures were grown in medium M199 alone. Media for experimental cultures were supplemented either with 100 µl ml-1 of CPH and CPS-carp GnRH (cultivated pituitary cell secretion affected by 10-6, 10-8, 10-10 M carp GnRH)....
متن کاملCentral and peripheral interleukin-1beta and interleukin-1 receptor I expression and their role in the acute stress response of common carp, Cyprinus carpio L.
In fish, the hypothalamus-pituitary-interrenal axis (HPI-axis), the equivalent of the hypothalamus-pituitary-adrenal axis (HPA-axis) in mammals, is activated during stress and leads to production and release of cortisol by the interregnal cells in the head kidney. In mammals, the cytokine interleukin-1beta (IL-1beta) takes a key position in the innate immune and inflammatory responses and influ...
متن کاملPituitary primary cell culture of Common carp (Cyprinus Carpio) and evaluation of its secretion effect on endocrine activity of incubated ovarian follicles
In this study, five carp pituitary glands were collected and dispersed enzymatically and mechanically.Then, the cells were cultivated as monolayer in MEM (minimum essential medium Eagle). The culture mediawere collected after 72 h and frozen at -20°C. Carp ovarian follicles also were separated mechanically andincubated in BSS (basic salt solution) Cortland medium in 24-well microplates for 48 h...
متن کامل