Lutropin regulation of steroidogenesis and specific protein synthesis in rat Leydig cells

In the testis steroidogenesis takes place in the Leydig cells (Hooker, 1970) and is under the control of lutropin, a glycoprotein hormone with a mol. wt. of about 30,000 consisting of 2 nonidentical subunits, which is secreted by the anterior pituitary (Hall, 1970). The main steroid secreted by the testis of the adult rat is testosterone (Eik-Nes, 1970). Cholesterol is the precursor for the synthesis of steroid hormones and its conversion into pregnenolone is stimulated by lutropin (Hall, 1970). The further conversion of pregnenolone into testosterone is not under the control of lutropin.