Testosterone secretion is affected by receptor tyrosine kinase c-Kit and anoctamin 1 activation in mouse Leydig cells

Receptor tyrosine kinase c-Kit, a marker found on interstitial cells of Cajal (ICCs), is expressed in Leydig cells, which are testicular interstitial cells. The expression of other ICC markers has not yet been reported. In this study, we investigated the expression of c-Kit and anoctamin 1 (ANO1), another ICC marker, in mouse testes. In addition, the relationship between c-Kit and ANO1 expression and Leydig cell function was investigated. We observed that c-Kit and ANO1 were predominantly expressed in mouse Leydig cells. The mRNA and protein of c-Kit and ANO1 were expressed in TM3, a mouse Leydig cell line. LH induced an increase in intracellular Ca2+ concentration, membrane depolarization, and testosterone secretion, whereas these signals were inhibited in the presence of c-Kit and ANO1 inhibitors. These results show that c-Kit and ANO1 are expressed in Leydig cells and are involved in testosterone secretion. Our findings suggest that Leydig cells may act as ICCs in testosterone secretion.