In vitro experiment, results showed the that the LH secretion of adenohypophysis incubated with Ginsenosides ( G ) and Pantoc-rine ( P ) was significantly increased, similar to the exciting effect of LRH which stimulats LH secretion. By addition of G or P and Indomethacin (an inhibitor of PGs synthesis) at the same time, however, the LH secretion was significantly decreased. It appears that PGs may be involved in the regulation of the exciting effect of G and P on LH secretion. The experiment in vivo also demonstrated that in healthy young male rats injected with P by S.c.,thetestosterone content in plasma had significant increase, that the binding capacity of testicular tissue to 125I-HCG (receptor function) did not change clearly.