Abstract: In order to reveal the effects of superior spermatic nerve (SSN) on adult rat testis， 25 Wistar rats were randomly divided into 2 groups. The experimental group rats were transected the SSN and samples were collected in the 30th after operation. The results demonstrated that testicular denervation had no obvious influence on testis mass(P＜0.05)，but significantly reduced cauda epididymal sperm counts（P＜0.01）. The immunostaining of proliferating cell nuclear antigen (PCNA) revealed that the denervation had no influence on the proliferarion of spermatogonium and primary spermatocyte，but changed the morphology of seminiferous tubules and the distribution of germ cells. In addition，RT-PCR results showed that testis denervation had no influence on the expression of testicular 3β-hydroxy sterol dehydrogenase (3β-HSD) mRNA，but significantly decreased testicular steroidogenic acute regulatory protein (StAR) and cholesterol-side-chain cleavage enzyme (P450scc) mRNA levels（P＜0.05）. These results suggested that SSN play an important role on the synthesis of testosterone and spermatogenesis through regulating the expression of adrenergic receptors，StAR and P450scc mRNA.

Key words: superior spermatic nerve; adrenergic receptors; synthesis of testosterone; spermatogenesis