抄録
The localization of βA subunit of inhibin/activin in rat testis was studied by means of immunohistochemistry using antibody raised against synthetic polypeptide. The intense reaction with anti-βA antibody was shown in the cytoplasm but not in the nucleus and the plasma membrane of spermatocytes. The reaction was also found in the cytoplasm of spermatids, through the immunostaining pattern was different between the two cells; the granule-like one in spermatocytes and diffused one in spermatids, respectively. Furthermore, the plasma membrane became positive in spermatids, suggesting that βA subunit may be produced in spermatocytes and secreted from spermatids. The expression of βA subunit in spermatogenic cells is thought to be stage-specific, because the reaction was not found in spermatogonia and spermatozoa. Although both Sertoli and Leydig cells are reported to produce βA subunit of inhibin/activin, no reaction was observed in these two cells. This suggests that the antibody used in this study may recognize the epitopes different from those detected by previously-used immunological probes.