endoplasmic reticulum membrane
The conversion of testosterone to the most potent androgen, 5-alpha-dihydrotestosterone (DHTEST), is catalyzed by microsomal 5alpha-steroid reductase 1 (SRD5A1) (Andersson & Russell 1990). SRD5A1 is expressed in the prostate and other androgen target sites. Corticotropin (Adrenocorticotropic hormone, ACTH) acts through melanocortin receptor type 2 (MC2R) to stimulate steroidogenesis, increasing the production of androgens (McKenna et al. 1997).