Incorporation of 7α- 3H-pregnenolone and 4- 14c-progesterone into corticosteroids and some of their ester sulfates by human newborn adrenal slices.

Abstract

Adrenal slices from a premature infant time of gestation: 22 weeks were incubated in the presence of equimolar amounts of 7α- 3H-pregnenolone (7 α- 3H-3β-hydroxypregn-5-en-20-one) and 4- 14C-progesterone (4- 14C-pregn-4-ene-3,20-dione). The incorporation of these two precursors into several steroids was studied as a function of the length of incubation 2.5 hrs. 17α-Hydroxyprogesterone (17α(-hydroxypregn-4-ene-3,20-dione), 11-deoxycortisol (17α(, 21-dihydroxypregn-4-ene-3, 20-dione) and cortisol (11β, 17α, 21-trihydroxypregn-4-ene-3, 20-dione) contained 14C and 3H in a ratio of 3.0–3.8, progesterone in a ratio of 31. 17-Deoxy-21-hydroxysteroids (11-deoxycorticosterone (21-hydroxy-pregn-4-ene-3, 20-dione) corticosterone (11β, 21-dihydroxypregn-4-ene-3, 20-dione) and their respective C-21 ester sulfates) contained low or undetectable amounts of 3H. Pregnenolone sulfate (20-ketopregn-5-ene-3β -y1 sulfate) and dehydroisoandrosterone sulfate (17-ketoandrost-5-ene-3β-yl sulfate) were characterized as the main biotransformation products of 7α- 3H-pregnenolone. The results are interpreted as illustrating pathways of steroid biogenesis leading to the formation of 17-hydroxy-corticosteroids from both progesterone and pregnenolone, the latter via 17α-hydroxypregnenolone (3β, 17α-dihydroxypregn-5-en-20-one), of 17-deoxycorticosteroids and some of their C-21 ester sulfates, mainly from progesterone and of steroids of the pregn-5-en and androst-5-ene-3β-y1 sulfate series from pregnenolone.