Objective: To investigate effect of of Xiaoyaosan on dopamine receptor cyclic adenosine monophosphate(cAMP)/proteinkinase A(PKA) signal transduction pathway in hyperprolactinemia(HPRL) rats. Method: The metoclopramide was injected to establish the animal model

48 SD rats were randomized into 6 groups:control group

model group

bromocriptine group

high dose modified Xiaoyaosan group

middle dose modified Xiaoyaosan group

low dose modified Xiaoyaosan group. The intervention period lasted 30 days. The immune histochemistry method to observe expression of PKA

D1R

D2R

ELISA method to observe expression of cAMP

fluorescent quantitative PCR method was used to observe expression of D1R and D2R. Result: Compared with the control group

modified Xiaoyaosan groups reduced PKA

cAMP activity(P < 0.01);dopamine D2 receptor was significantly increased(P < 0.01). Conclusion: The modified Xiaoyaosan can regulate the PRL level through dopamine receptor cAMP/PKA signal transduction pathway.