Nitric oxide synthase expression in eutopic and ectopic endometrial of women with endometriosis

Objective:To explore the expression of endothelial and inducible nitric oxide synthase(eNOS and iNOS) in eutopic and ectopic endometrial of women with endometriosis.Methods:Reverse transcriptase polymerase chain reaction(RT-PCR) was performed on endometriosis tissues obtained from controls (n=20) and on eutopic/ectopic endometriosis tissues from endometriosis patients (n=30) to evaluate eNOS and iNOS concentrations in these endometriosis tissues.Results:eNOS were expressed in both endometrial hyperplasia period and secretion period. In endometrial hyperplasia period in eutopic/ ectopic endometriosis tissues , the eNOS concentrations were 2.47±0.38/2.53±0.51,and it was 1.73±0.50 in control group; In the secretion period in eutopic / ectopic endometriosis tissues, the eNOS concentrations were 3.37±0.4/3.43±0.44, and it was 3.16±0.55 in control group. The expression of eNOS in endometrial hyperplasia period were higher in the endometrial tissues of women with endometriosis than that in control group (P=0.01), the expression of eNOS was no significant in endometrial hyperplasia period. iNOS only had a micro-expression in secretion period, in eutopic/ ectopic endometriosis tissues , the eNOS concentrations were 1.17±0.22/1.33±0.28, it was 0.86±0.24 in control group. Endometriosis appeared to contain more iNOS than those of controls in secretion period (P=0.016).The expression of eNOS and iNOS in eutopic/ ectopic endometriosis tissues had no significance in different stage during the menstrual cycle compared with the EC juice (P values were 0.25,0.106,0.073).Conclusion:Greater amounts of NOS are present in the endometrial tissues of women with endometriosis, implying a possible role for NOS in the pathogenesis of endometriosis.