Pregnenolone, 3beta-Hydroxypregn-5-en-20-one is an endogenous steroid hormone involved in the steroidogenesis of progestogens, mineralocorticoids, glucocorticoids, androgens, and estrogens, as well as the neuroactive steroids. As such it is a prohormone, though it also has biological effects of its own, behaving namely as a neuroactive steroid in its own right with potent anxiolytic effects. Pregnenolone is synthesized from cholesterol. This conversion involves hydroxylation at the side-chain at C20 and C22 positions, with cleavage of the side-chain. The enzyme performing this task is cytochrome P450scc, located in the mitochondria, and controlled by anterior pituitary tropic hormones, such as ACTH, FSH, LH. To assay conversion of cholesterol to pregnenolone, radiolabelled cholesterol has been used. Pregnenolone product can be separated from cholesterol substrate using Sephadex LH-20 minicolumns.
