Stage dependent and androgen inductive expression of orphan receptor TR4 in rat testis.

In this study, we investigated the expression of TR4 in different stages of seminiferous tubules and the relationship between TR4 and androgen in rat testis. We found that TR4 was stage-dependently expressed in rat seminiferous tubules, T withdrawal induced by high doses of testosterone undecanoate and ethane dimethane sulfonate inhibit TR4 expression in rat testis, and testosterone induced TR4 expression in co-cultured primary germ/Sertoli cells. Furthermore, we demonstrated that androgen receptor could enhance TR4-mediated transactivation activity in testis cells in the presence of testosterone. Together, these data indicate that the expression of TR4 in rat testis is stage dependent and androgen inductive, and suggest the important role of orphan receptor TR4 in spermatogenesis.