ESTROGENS POTENTIATE THE STIMULATORY EFFECTS OF FOLLICLE-STIMULATING-HORMONE ON N-CADHERIN MESSENGER-RIBONUCLEIC-ACID LEVELS IN CULTURED MOUSE SERTOLI CELLS

Gonadal steroids and FSH are key regulators of Sertoli cell function. N-Cadherin (N-cad) is a calcium-dependent cell adhesion molecule that mediates Sertoli cell-germ cell interactions. We recently demonstrated that steroids, in particular estradiol, are potent regulators of test icular N-cad messenger RNA (mRNA) levels in vivo. In view of the coope rative effects of steroids and FSH on Sertoli cell-germ cell interacti ons, we examined the combined effects of these hormones on N-cad mRNA levels in cultured mouse Sertoli cells. FSH was capable of increasing N-cad mRNA levels 2-fold in these cells. The effects of FSH on N-cad m RNA levels in cultured Sertoli cells were mimicked by cAMP-inducing ag ents. Treatment of the Sertoli cell cultures with FSH and estradiol st imulated N-cad mRNA levels 3-fold, whereas steroids alone had no effec t on N-cad mRNA levels. These studies demonstrate that FSH and estradi ol in combination are required to achieve maximal N-cad mRNA levels in cultured Sertoli cells. The results obtained from these studies subst antiate the hypothesis that estrogens play a pivotal role in regulatin g spermatogenesis.