抄録
Activin, a member of the transforming growth factor-β superfamily, has recentlybeen isolated from eel testicular cDNA library. Using an in vitro testicular organ culture system, we investigated the effect of human recombinant activin A and B in eel spermatogenesis. Addition of human recombinant activin A and B (10 ng and 100 ng/ml) to the culture medium induced proliferation of spermatogonia within 15 days in the same manner as addition of 11-ketotestosterone (10 ng/ml) for positive control. In cultured testes without activins, however, the proliferation of spermatogoniawas not observed. Although it is necessary to investigate the eel's own activin A and B protein, these results suggest the possibility that activin induces initiation of spermatogenesis in Japanese eel.
