FUNCTIONAL INTERACTIONS BETWEEN THE SOMAT IC-CELLS IN THE MALE GONAD

The existence of multiple interactions between somatic cells in the te stis, has been suspected in vivo, and demonstrated in vitro by cocultu res and cultures in the presence of conditioned media. Long term Serto li-Leydig cell interactions results in a local regulation of the speci fic differenciated functions of these cells, and more precisely in a c ontrol of their responsiveness to their respective gonadotropin. Among the paracrine and/or autocrine factors, growth factors are involved i n the control of differentiated functions. It is the case for IGF-I an d TGF-B, which respectively exhibit a stimulatory and inhibitory effec t on Leydig cell functions and more specifically on LH responsiveness.