Control of androgen cytosol receptor concentrations in Sertoli cells: effect of androgens

Androgen receptor concentrations were measured in Sertoli cells under a variety of conditions. After brief (30- to 60-min) incubation of cultured cells with [3H]R1881 (methyltrienolone), cytosol receptor concentrations were greatly diminished, and nuclear bound steroid was elevated. Removal of the exogenous steroid was accompanied by a return of cytosol receptor to preincubation concentrations by 1 h and a slower decline in nuclear bound steroid. In the continued presence of R1881 or testosterone, cytoplasmic receptor concentrations declined and then returned to or above preincubation concentrations by 6-17 h. Actinomycin-D and cycloheximide did not alter this pattern. Over this same interval, nuclear bound steroid concentrations remained elevated. Exposure of the cells to R1881 or testosterone for the entire 72-h culture period did not alter cytoplasmic receptor concentrations. Cytoplasmic androgen receptor concentrations were decreased in Sertoli cells from hypophysectomized rats 15-22 days after surgery compared to those in cells from intact controls. Treatment with testosterone propionate (0.5 mg/day) or FSH (75 micrograms/day) prevented the decline in receptor concentrations. Cryptorchidy (33 days) also decreased cytosol receptor concentrations. These data indicate that exposure to androgens can influence Sertoli cell cytosol androgen receptor concentrations in vitro and in vivo. The Sertoli cell adapts to the continual presence of androgens with a return of cytosol receptor while maintaining elevated concentrations of nuclear bound steroid. In vivo, androgen treatment can maintain cytoplasmic receptor concentrations in the absence of pituitary hormones in the immature rat.