Analysis of Endomorphin-1 and Endomorphin-2 in Peripheral Blood of Postmenpausal Women with Long-term Low-dose Hormone Replacement Therapy

Abstract

Abstract: Objective To investigate the levels of EM^-1 and EM^-2 in peripheral blood with long-term low dose HRT therapy and analyze the relationship between endomorphins and estradiol. Methods 169 female medical staff in Peking Union Medical College Hospital were included in our study. Based on age, participants were divided into 4 groups, including 50~59 , 60~64 , 65~69 and over 70 years old , HRT group and control group were included in each age group. Plasma hormones including estradiol (E2), progesterone (P) and testosterone (T) were detected by using Bio-RAD 550 Model ELISA(enzyme-linked immunosorbent assay) device, and levels of EM^-1 and EM^-2 were examined by radioimmunoassay methods. Results Compared to control group at each age, plasma estrodiol (E2) levels obviously increased in HRT groups (P<0.05). The levels of EM^-1 and EM^-2 in HRT group of each age decreased compared to control group, meanwhile, pearson correlation analysis showed that the level of endomorphin^-1 (EM^-1) on all subjects was correlated with their individual estradiol(P<0.01). Conclusion This is the first observation of the relationship between endomorphins and estradiol in a long-term low-dose HRT therapy, which providing clinical significance of protecting brain cognition in postmenpausal women.

Key words: hormone replacement therapy(HRT), endomorphin-1(EM-1), endomorphin-2(EM-2)

CLC Number:

R969.4

WANG Tao, REN Zhi-li, JI Chao, YANG Nan, LIU Yan-yong, ZUO Ping-ping. Analysis of Endomorphin-1 and Endomorphin-2 in Peripheral Blood of Postmenpausal Women with Long-term Low-dose Hormone Replacement Therapy[J]. Chinese Journal of Pharmacovigilance, 2016, 13(4): 212-215.

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