BOTH SERTOLI AND PERITUBULAR CELLS RESPOND TO ANDROGENS WITH INCREASED EXPRESSION OF AN ANDROGEN RESPONSE ELEMENT REPORTER

To explore the ability of androgens to affect gene expression in Serto li and peritubular cells in vitro, constitutively expressed pSV(2)-Luc and a regulated reporter containing an androgen response element (MMT V-Luc) were transiently transfected into these cells. Reporter express ion was markedly affected by cell density and maturational age. Mibole rone-stimulated MMTV-Luc expression increased in Sertoli cells with an imal age between 15 and 25 days, consistent with the developmental inc rease in androgen receptor concentration, but was not markedly age-dep endent in peritubular cells. The antiandrogen hydroxyflutamide inhibit ed stimulation of MMTV-Luc expression by 1 and 10 nM testosterone in b oth Sertoli and peritubular cells, consistent with an androgen recepto r-mediated event. In contrast, dexamethasone at 1 and 10 nM elicited n o effect in Sertoli cells, but stimulated MMTV-Luc expression in perit ubular cells. In this study, the androgen receptor/glucocorticoid rece ptor ratio was 2.4 and 0.06 in Sertoli and peritubular cells, respecti vely Cotransfection of Sertoli and peritubular cells with a plasmid ex pressing the rat androgen receptor further increased the androgen-stim ulated expression of MMTV-Luc. These data demonstrate the functionalit y of the androgen receptors in both Sertoli and peritubular cells in c ulture. Receptor expression appears to be a limiting factor in the res ponse. The data are consistent with potential roles for both Sertoli a nd peritubular cells in androgen-mediated transcriptional events in th e testis.