Abstract
Aim: We examined the effect of anti-Müllerian hormone (AMH) on the expression of gonadotropin subunits in pituitary gonadotrophs.Methods: The mouse pituitary gonadotroph cell line LβT2 was stimulated with AMH and the expression levels of gonadotropin subunits were determined by real-time PCR. We also examined the involvement of the Kiss-1 gene (encoding kisspeptin) and the kisspeptin receptor (Kiss-1R) in LβT2 cells. Results: A significant increase was observed in the expression level of the FSHβ subunit with AMH but not in the expression levels of gonadotropin α and LHβ subunits. A significant decrease was observed in the expression of Kiss-1 and Kiss-1R genes in LβT2 cells with AMH stimulation. Kiss-1 gene knockdown by siRNA did not alter the basal expression of gonadotropin subunits. When LβT2 cells overexpressing Kiss-1R were stimulated with kisspeptin, there was a significant increase in the gene expression levels of the gonadotropin subunits α, LHβ, and FSHβ. This inductive effect of kisspeptin was almost completely inhibited by AMH pretreatment. The GnRH-induced increase in gonadotropin subunit genes was unchanged in the presence of AMH. Conclusions: AMH can increase FSHβ subunit gene expression in pituitary gonadotroph cells. However, AMH decreases Kiss-1 and Kiss-1R gene expression within the gonadotrophs. Because AMH pretreatment abolishes kisspeptin-induced expression of gonadotropin subunit genes, AMH may control kisspeptin-regulated gonadotropin expression by inhibiting the expression and function of Kiss-1R within gonadotrophs.