Abstract: To investigate the Elastin and 1ysyl oxidase（LOX）expressions in the cardinal ligament of premenopausal women with pelvic organ prolapse（POP）so as to determine the alteration that contributes to POP. MethodsCardinal ligament samples were obtained from 42 premenopausal POP subjects and 27 non POP control women that underwent a hysterectomy. Reverse transcription polymerase chain reaction（RT-PCR）was used to verify the mRNA level of Elastin and LOX. The concentration of Elastin and LOX was determined by the Western blotting technique, electrophoretic separation and quantification. Results The POP group demonstrated a significant decrease of expressions of Elastin and LOX in the cardinal ligament than in the control group (P＜0.05). There was an identical tendency in protein level of these two groups (P＜0.05). Also, there was a positive correlation between the two groups（P＜0.05）. ConclusionThe significant decrease in Elastin production in the cardinal ligaments may lead to a loss of functional tissue elasticity, a condition that may progress to the development of POP, and collagen and elastin metabolism in POP is altered by LOX. This alteration results in less flexible connective tissue, which is probably more likely to break. LOX might be involved in the pathogenesis of POP.

Key words: Pelvic organ prolapse, Elastin, Proteinlysine 6-oxidase