RESUMEN
<p><b>OBJECTIVE</b>To establish a primary culture method of rat testis Leydig cell.</p><p><b>METHODS</b>The primary rat Leydig cells were treated with or without 4 U/ml human chorionic gonadotropin (hCG), and testosterone in culture medium was detected by radioimmunoassay. The morphology and biological characteristics of Leydig cell were observed.</p><p><b>RESULTS</b>The culture cells were highly homogeneous, proliferative and had a high differentiation rate. The high purified Leydig cells were verified by their dynamic morphological changes and 3beta-hydroxysteroid dehydrogenase delta4-delta5 isomerase (3beta-HSD) histochemical staining. The testosterone secretion induced by hCG significantly increased (P < 0.05) 24 hours after inoculation than that induced without hCG in the control.</p><p><b>CONCLUSION</b>It suggests that the Leydig cell cultured in vitro may secrete high concentration of testosterone, and this study laid the basis of androgen replacement therapy for partial androgen deficiency in aging male.</p>