Steroidogenic Function Of Leydig Cells

The primary function of Leydig cells is to synthesize and secrete androgenic steroids. The process of androgen biosynthesis requires the activities of four enzymes: cytochrome P450 cholesterol side chain cleavage enzyme (P450scc), 3P-hydroxysteroid dehydrogenase/A5-4 isomerase (3P-HSD), cytochrome P450 17a-hydroxylase (P45017a), and 17P-hydroxysteroid dehydrogenase (17P-HSD) (35). Leydig cells are the only cells in the testis containing P450scc and 3P-HSD. Thus, Leydig cells are the sole tes-ticular location for the first two steps in steroidogenesis converting cholesterol, the substrate for all steroid hormones, to pregnenolone and pregnenolone to progesterone (36-38). Thereafter, with the catalytic activities of P45017a and 17P-HSD, steroidogenesis proceeds to the ultimate product, testosterone (39). The synthetic process involves three hydroxylations (at carbons 17, 20, and 22), two cleavages (at carbons

20-22 and 17-20), two dehydrogenations (3P,17P), and one A5-4 isomerization (the steroidogenic pathway is shown in Fig. 4).

Was this article helpful?

0 0
Eliminating Stress and Anxiety From Your Life

Eliminating Stress and Anxiety From Your Life

It seems like you hear it all the time from nearly every one you know I'm SO stressed out!? Pressures abound in this world today. Those pressures cause stress and anxiety, and often we are ill-equipped to deal with those stressors that trigger anxiety and other feelings that can make us sick. Literally, sick.

Get My Free Ebook


Post a comment