Objective:Toinvestigate the effect of ATP50 on GH-induced testosterone secretion in isolated SD rat Leydigcells.Methods:The Leydig cells were treated with ATP50 antisense oligodeoxynucletides(Anti-ODN)in GH group

nonsense tat ODN in control group

cAMP and testosterone in culture medium was detected by radioimmunoassay

expression of ATP50 protein was investigated by immunohistochemistry.Results:Antisense ATP50 ODN significantly inhibited GH-induced testosterone secretion of isolated rat Leydig cells in a dose-dependent manner(P<0.05).At the same time

integral optical density immunostaining of ATP50 protein in Leydig cells was also remarkably reduced.Nonsense tat ODN had no effect on GH-induced testosterone secretion of Leydig cells

integral optical density immunostaining of ATP50 was remarkably more obvious in nonsense tat ODN group than in GH group(P<0.05).Conclusion:These results indicate that ATP50 might closely correlate with GH-reduced testosterone secretion.