Dexamethasone and aldosterone modulate corticotropin-releasing factor-41 release from cultured rat fetal hypothalamic cells through type II and type I corticosteroid receptors respectively.

Dexamethasone and aldosterone inhibit hypothalamic corticotropin releasing factor-41 (CRF) release. The possible receptors through which these adrenal steroids affect CRF release were studied using rat fetal hypothalamic cell cultures. Neither the antimineralocorticoid RU 28318 nor the antiglucocorticoid RU 38486 alone had any effect on forskolin-stimulated CRF release. RU 38486 and RU 28318 however suppressed dexamethasone (1 microM)- and aldosterone (1 microM)-induced inhibition of forskolin (20 microM)-stimulated CRF release, respectively, suggesting that dexamethasone and aldosterone reduce CRF release through type II and type I corticosteroid receptors, respectively. RU 38486 had no effect on aldosterone-induced inhibition of forskolin-stimulated CRF release, nor did RU 28318 have any effect on dexamethasone-induced inhibition of forskolin-stimulated CRF release, indicating specificity of the binding of aldosterone with type I receptors, and dexamethasone with type II receptors in the hypothalamic cell cultures.