These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.
Pubmed for Handhelds
PUBMED FOR HANDHELDS
Search MEDLINE/PubMed
Title: Induction of cultured bovine adrenocortical zona glomerulosa cell 17-hydroxylase activity by ACTH. Author: Crivello JF, Gill GN. Journal: Mol Cell Endocrinol; 1983 Apr; 30(1):97-107. PubMed ID: 6301909. Abstract: The induction of steroid 17-hydroxylase activity was examined in primary cultures of bovine adrenocortical zona glomerular cells. 17-Hydroxylase activity was determined by assaying the metabolism of [3H]pregnenolone to [3H]17-hydroxypregnenolone by high performance liquid chromatography (HPLC). Conversion of [3H]pregnenolone to [3H] progesterone and [3H]17-hydroxypregnenolone to [3H]17-hydroxyprogesterone was prevented by the addition of cyanoketone, an inhibitor of 3 beta-hydroxysteroid dehydrogenase. ACTH increased adrenal zona glomerulosa 17-hydroxylase activity 55-fold to 1750 pmoles/10(4) cells/2 h, an activity equivalent to that of ACTH-treated zona fasciculata cells. Maximal induction was seen after 4 days exposure to ACTH. The dose of ACTH which gave half-maximal induction was 0.25 nM. Previously, ACTH had been demonstrated to suppress bovine glomerulosa conversion of deoxycorticosterone to aldosterone by a steroid-induced oxygen-derived free radical process that was prevented by antioxidants. This process resulted in loss of the terminal cytochrome P-450 enzyme involved in aldosterone biosynthesis. However, induction of 17-hydroxylase activity is not affected by antioxidants or the addition of steroids, e.g. cortisol. ACTH-mediated induction of bovine zone glomerulosa 17-hydroxylase activity and suppression of glomerulosa aldosterone production results in effective conversion of functional glomerulosa cells to functional fasciculata cells. The actions of ACTH on glomerulosa 17-hydroxylase activity support the hypothesis of a steroid-induced functional zonation of the adrenal cortex.[Abstract] [Full Text] [Related] [New Search]