Mesonephric excretory function related to its influence on differentiation of fetal gonads.

The mammalian intermediate fetal kidney, the mesonephros, is known in different species to excrete body waste products during a limited period of fetal life. Recently, the mesonephros and its derivatives have been shown to influence gonadal functions in several ways. Thus, the mesonephric cells are responsible for regulating the onset of meiosis in different mammals by the secretion of two substances, a meiosis-inducing substance (MIS) and a meiosis-preventing substance (MPS). In this paper, the relation between mesonephric kidney function and its influence on the gonads is reviewed through literature studies. It seems that cessation of mesonephric excretion precedes onset of meiosis in the ovary in different species. It is suggested that the mesonephric renal function interferes with synthesis and/or secretion of MIS or that the excreted products may interfere with the responsiveness to MIS of the germ cells.