OBJECTIVETo explore the specific regulative law of electroacupuncture (EA) for the hypothalamus-pituitary-gonad axis.

METHODSThe adult female SD rats were divided into a simulant EA group, Guanyuan (CV 4) group and Neiguan (PC 6) group according to 4 stages of the estrous cycle. Acupuncture was given from 9 : 30 AM to 10 : 00 AM and the brain tissue samples were collected at 15 : 00 PM. GnRH expressions in the nuclei related with genital neuroendocrine in the hypothalamus were investigated with immunohistochemical method.

RESULTS(1) The GnRH expression quantity was different in different estrous cycles in the simulant EA group, with more expression in the proestrus and the estruation; (2) After acupuncture, the GnRH expressions in the medial preoptic area, the arcuate nuclei and the nuclei periventriculares were increased in different stages of the estrous cycle in varying degrees, with the "strong" GnRH expression increased significantly in the diestrus and the metaoestrus in the Guanyuan (CV 4) group.

CONCLUSIONAfter EA, the expression of the GnRH-positive reactant in the medial preoptic area, the arcuate nuclei and the nuclei periventriculares of the hypothalamus significantly increases, with the Guanyuan (CV 4) group better than the Neiguan (PC 6) group, and more obvious expressions in the diestrus and the metaoestrus.