Many parvocelular neurons in the paraventricular nucleus of the hypothalamus express high levles of conticotropin releasing factor (CRF) or vasopressin following adrenalectomy. To determine whether gulcocorticoid receptor was used in cobination with polyclonal antisera directed against either vasopressin or CRF to permit simultanrous visulization of either peptide with gulcocorticiod receptor‐like immunoreactivity (IR). Rats were adrenlectomized (ADX) for 2 weeks to optimize numbers of vasopresin‐and CRF‐IR neurons. Six hours prior to sacrifice, a seprate group of adrenalectomized rats was treated with conticosterone (40 mg/kg). This short‐term re‐placement resulted in nuclear localization of gulcocorticoid receptor‐like‐IR but did not attenuate the increased numbers of CRF‐ and vasopressin‐Ir neurons observed after adrenlectomy. It was therfore possible to visualize vasopressin‐ or CRF‐IR and nuclear glucocorticoid receptor‐like‐Ir simultancously. Cell counts of deouble‐labeled neurons studied, which respond to adrenlectomy by increased peptide expression. Thse data suggest that a major feedback effect of gulcocorticoids on the hypothalamic‐pituitary‐adrenal axis is exerted directly within nuclei of CRF and vasopressin neurons.
- setroid receptors