NP-21 Effects and Mechanisms of Estrogen on Endogenous Growth Hormone in Brain of Ovariectomized Rats

Objective:To observe the effects of estrogen/plant estrogen(Biochanin A,BCA)on learning and memory of ovariectomized rats,so as to explore the possible mechanisms of neuroprotective effect on endogenous growth hormone.Method:A total of 50 six-month-old female rats were randomly divided into five groups:sham group,model group,17β-estrodiol,Biochanin A high-dose group,and low-dose group.The changes of the spatial learning and memory function were observed through Morris water maze and shuttle box.After the treatment,morphological structures of rat neurons were observed by HE staining and electron microscopy.The contents of E2 and GH in serum were determined by ELISA and associated proteins of growth hormone JAK/STAT signaling pathway were examined by western blot.Result:Estrogen/BCA could enhance learning and memory ability of the aging rats,improve the structures of the nerve cells,increase E2,GH and IGF1 levels,improve STAT5 and p-STAT5 protein expression and reduce SOCS2 protein expression.Conclusion:Estrogen/BCA could significantly improve memory dysfunction,the mechanisms may be related to increase secretion of endogenous growth hormone,regulate growth hormone JAK/STAT signaling pathway.