Expression of nerve growth factor (NGF), and its receptors TrkA and p75 in the reproductive organs of the adult male rats.

Immunolocalization of nerve growth factor (NGF) and its receptors, TrkA and p75 in the reproductive organs of adult male rats was investigated. Sections of the testis, efferent duct, epididymis, deferent duct, seminal vesicle, coagulating gland and prostate of adult male rats were immunostained by the avidin-biotin-peroxidase complex methods (ABC). NGF was expressed in Leydig cells, primary spermatocytes and pachytene spermatocytes in the testis. TrkA only immunoreacted to elongate spermatids and p75 showed positive immunostaining in the Sertoli cells, Leydig cells, the pachytene spermatocytes and elongate spermatids. Immunoreactions for NGF and its two receptors were detected in epithelial cells of efferent duct, deferent duct and epididymis. In addition, immunoreactions for NGF and its two receptors were also observed in columnar secretory epithelium lines of the seminal vesicles, prostate and coagulating gland. These results suggest that NGF is an important growth factor in gonadal function of adult male rats.