M Hickey1, J Higham, M Sullivan, L Miles, I S Fraser. 1. Department of Obstetrics and Gynecology at St. Mary's, Imperial College School of Medicine, London, England, UK. m.hickey@ic.ac.uk
Abstract
OBJECTIVE: To establish the effect of hormone replacement therapy (HRT) on the expression of matrix metalloproteinase 9 (MMP-9) and the tissue inhibitor of MMPs, TIMP-1, in the endometrium of postmenopausal and perimenopausal women. DESIGN: Prospective observational study. SETTING: United Kingdom teaching hospital. PATIENT(S): Thirty-one perimenopausal and postmenopausal HRT recipients, with a control group of eight postmenopausal women not undergoing HRT. INTERVENTION(S): Prospective record of bleeding patterns and endometrial biopsy. MAIN OUTCOME MEASURE(S): Endometrial histology, bleeding patterns, MMP-9, and TIMP-1 expression. RESULT(S): MMP-9 and TIMP-1 are expressed in benign postmenopausal endometrium. Expression of both molecules is reduced in HRT recipients compared with non-HRT recipients. CONCLUSION(S): Exposure to HRT appears to alter endometrial expression of MMP-9 and TIMP-1 and also the local balance between these molecules. This alteration may promote breakdown of the endometrial extracellular matrix and blood vessels and hence bleeding.
OBJECTIVE: To establish the effect of hormone replacement therapy (HRT) on the expression of matrix metalloproteinase 9 (MMP-9) and the tissue inhibitor of MMPs, TIMP-1, in the endometrium of postmenopausal and perimenopausal women. DESIGN: Prospective observational study. SETTING: United Kingdom teaching hospital. PATIENT(S): Thirty-one perimenopausal and postmenopausal HRT recipients, with a control group of eight postmenopausal women not undergoing HRT. INTERVENTION(S): Prospective record of bleeding patterns and endometrial biopsy. MAIN OUTCOME MEASURE(S): Endometrial histology, bleeding patterns, MMP-9, and TIMP-1 expression. RESULT(S): MMP-9 and TIMP-1 are expressed in benign postmenopausal endometrium. Expression of both molecules is reduced in HRT recipients compared with non-HRT recipients. CONCLUSION(S): Exposure to HRT appears to alter endometrial expression of MMP-9 and TIMP-1 and also the local balance between these molecules. This alteration may promote breakdown of the endometrial extracellular matrix and blood vessels and hence bleeding.