IMMUNOLOCALIZATION OF RECEPTORS FOR ANDROGEN AND ESTROGEN IN MALE CAPRINE REPRODUCTIVE TISSUES - UNIQUE DISTRIBUTION OF ESTROGEN-RECEPTORS IN EFFERENT DUCTULE EPITHELIUM

Androgens and estrogens affect physiological processes in the testis a nd male excurrent duct system. This study was designed to identify and characterize distribution of androgen receptors (AR) and estrogen rec eptors (ER) in the reproductive organs of the male goat. Tissues, incl uding testis, efferent ductules, epididymis (regions I-V), and ductus deferens, were obtained from five mature Nubian goats, fixed in 4% par aformaldehyde, and embedded in paraplast. Antigenic sites for AR were unmasked by microwave treatment (four times, 5 min each) of tissue sec tions immersed in 10 mM citrate (pH 6) and were detected using the PG- 21 rabbit anti-rat/human antibody. Antigenic sites for ER were identif ied using the H-222 rat anti-human monoclonal antibody after tissue se ctions were treated with pronase (0.5 mg/ml, 37 degrees C, 8 min). Avi din-biotin horseradish peroxidase procedures were used to identify pos itive immunoreactivity, irrelevant IgG was substituted for primary ant ibody in negative controls. Positive nuclear immunostaining for AR was observed in all types of epithelial cells, peritubular smooth muscle cells, and intertubular fibroblasts of the intratesticular rete, effer ent ductules, epididymis (regions I-V), and ductus deferens, as well a s in Sertoli, Leydig, and peritubular myoid cells and intertubular fib roblasts of the testis. In contrast, nuclear immunostaining for ER was confined to nonciliated cells of the efferent ductules. Thus, AR-posi tive cells are ubiquitously distributed in caprine testicular and excu rrent ductular tissues, and ER-positive cells are unique to the effere nt ductules. The caprine model should be useful in studies designed to determine mechanisms through which androgens and estrogens regulate d evelopment and function of the testes and excurrent ducts.