Gene expression changes of urokinase plasminogen activator and urokinase receptor in rat testes at postnatal stages.

Aim: To investigate the gene expression changes of urokinase plasminogen activator (uPA)/urokinase receptor (uPAR) in rat testes at postnatal stages and explore the effects of uPA/uPAR system on the rat spermatogenesis. Methods: The mRNAs of uPA and uPAR in rat testes were measured by using real-time quantitative polymerase chain reaction (PCR) at postnatal days 0, 5, 10, 15, 21, 28, 35, 42, 49 and 56, respectively. Results: The tendencies of uPA and uPAR mRNA expression were similar at most postnatal stages except for D0. The expression of uPAR mRNA in rats testes was relatively higher than that of uPA at postnatal D0, and both were decreased until D21, increased obviously at postnatal D28, reached a peak at postnatal D35, then declined sharply at postnatal D42 and retained at a low level afterwards. Conclusion: The uPA/uPAR system may be strongly linked to spermiation and spermatogenesis via regulating germ cell migration and proliferation, as well as promoting the spermiation and detached residual bodies from the mature spermatids. (Asian J Androl 2007 Sep; 9: 679–683)