Comparison of androgen biosynthesis in isolated leydig cells from rat and mouse testis: incubation and superfusion...

Production of testosterone by highly purified Leydig cells prepared from rat and mouse testes is compared. Testosterone formation is improved to a higher degree in rat (2.7-fold) than in mouse (1.7-fold) cells by collagenase treatment of the testis compared with mechanical isolation. Mouse Leydig cells respond to exogenous stimuli (choriogonadotropin, dibutyryl cyclic AMP) with 2.4-fold higher testosterone secretion than rat cells. A 1.7-fold increased conversion of androgen precursors to testosterone by mouse compared with rat Leydig cells is demonstrated in static incubations as well as in steady-state superfusion experiments and can be derived from enhanced androstenedione reduction and a less inhibitory effect of progesterone on this process in mouse Leydig cells.