In vitro steroid biosynthesis by the adrenal gland of the female Lacerta vivipara Jacquin: the metabolism of exogenous precursors.

The synthesis of steroids in vitro by adrenal glands from female Lacerta vivipara J., using various labeled steroids as substrates, was studied. Effects of two enzymatic inhibitors (cyanoketone and elipten) on steroid synthesis was analyzed. As in other reptilian species, no 17-hydroxycorticosteroids were detected and the major biosynthetic pathway operating in vitro proved to be that of 17-deoxycorticosteroids. An important synthesis of an unidentified compound (X) was observed only from pregnenolone. Incubations of L. vivipara adrenal glands have been performed using [3H]pregnenolone plus [14C]progesterone at different phases of the annual cycle. Changes in adrenal steroid activity, related to season and physiological state of female, are quantitative rather than qualitative. High production in vitro of progesterone and 18-hydroxycorticosterone is associated with gestation whereas high production of deoxycorticosterone and corticosterone is observed during hibernation.