Glucocorticoid regulation of androgen binding protein expression in primary Sertoli cell cultures from rats

Glucocorticoids are known to inhibit testicular function, and its receptor is also localized in the Sertoli cells. To evaluate possible role of glucocorticoid in Sertoli cells, the effects of dexamethasone on the expression of androgen binding protein (ABP) have been investigated in primary Sertoli cell cultures. Dexamethasone increased ABP mRNA levels, with maximal stimulation reached at 36 hr. The induction of ABP mRNA was dependent on the low concentration (10(-8) and 10(-7) M) of dexamethasone but gradually reduced in the cells treated with high concentration (10(-6) and 10(-5) M). Dexamethasone-induced ABP mRNA level was no change in the cells after addition of cycloheximide but almost reduced by actinomycin-D pretreatment. Steady-state levels of ABP mRNA gradually increased in the Sertoli cells prepared from 14- and 21-days of age corresponding to rat puberty, and ABP mRNA was induced by dexamethasone. These results suggest that ABP gene is transcriptionally regulated by dexamethasone in primary Sertoli cell cultures.