LHRH, the role of LHRH (agonists) in the regulation of gonadal function

Studies which have contributed to the present knowledge about peripheral effects of LHRH agonists are reviewed and compared with studies on the mechanism of effects of LHRH on the pituitary gland. It is concluded that LHRH or LHRH agonists can directly stimulate or inhibit the activity of gonadal cells from rats but not from man. Effects of LHRH on other human or rat peripheral tissues have been observed. LHRH- or LHRH-like molecules can be isolated from rat testes, but there is not enough evidence to consider LHRH- or LHRH-like peptides as general and important paracrine factors for regulation of gonadal function. On the other hand studies with LHRH agonists have stimulated investigations on cell-cell interactions in the gonads and data have been collected which show that peptides which are less or non-related to LHRH can modulate functional properties of gonadal cells via pathways not employed by gonadotropins.