Journal of Molecular Endocrinology (1991) 6, 249-255 DOI: 10.1677/jme.0.0060249
© 1991 Society for Endocrinology
Self-inhibition of steroid secretion by amphibian adrenocortical cells is not mediated through glucocorticoid receptors
P. Netchitailo,
A. Larcher,
F. Leboulenger,
M. Feuilloley,
D. Philibert and
H. Vaudry
To investigate a possible direct action of glucocorticoids on adrenal steroidogenesis, the effect of corticosterone on the conversion of pregnenolone into various metabolites by frog adrenal tissue was examined. Frog interrenal slices were incubated with [3H]pregnenolone (1 mCi/ml) and the various labelled metabolites analysed by reverse-phase high-performance liquid chromatography. With the methanol gradient used, five identified steroids were resolved: progesterone, 11-deoxycorticosterone, corticosterone, 18-hydroxycorticosterone and aldosterone. Corticosterone (10 µg/ml) induced a 45–80% decrease in all steroids synthesized from [3H]pregnenolone. In contrast, the glucocorticoid agonist dexamethasone did not reduce the rate of conversion of pregnenolone into its metabolites. In addition, the inhibitory effect of corticosterone was not reversed by the specific glucocorticoid antagonist RU 43044. These results show that corticosterone exerts a direct inhibitory effect on adrenal steroid secretion. In addition, our data indicate that the ultra-short regulation induced by corticosterone is not mediated through glucocorticoid receptors.
Copyright © 1991 by the Society for Endocrinology.