Clinical Significance of Neuropeptide Y Expression in Pelvic Tissue in Patients with Pelvic Floor Dysfunction

OBJECTIVES: To investigate the neuropeptide Y (NPY) expression in the tissue of pelvic floor ligament and anterior vaginal wall in female patients with pelvic organ prolapse (POP) and stress urinary incontinence (SUI). METHOD: Seventeen patients with POP, 6 with SUI, 13 with POP and SUI (POP&SUI), and 10 controls were included in this study from First Affiliated Hospital of JiNan University. Immunohistochemical assay was used to examine NPY expression in the tissue of round ligament, cardinal ligament of uterus, uterosacral ligament, and anterior vaginal wall. NPY expression were compared between POP, SUI, POP&SUI and controls. RESULTS: NPY was positive expressed in the round ligament, cardinal ligament of uterus, uterosacral ligament, and anterior vaginal subepithelial connective tissue. Compared with the control group, NPY expression in the round, cardinal, and uterosacral ligaments in patients with POP&SUI group was decreased with significant statistical difference (p<0.05). NPY expression in anterior vaginal wall was significantly decreased in POP, SUI, and POP&SUI groups compared to normal group (p<0.05). Compared to POP group, NPY expression in SUI and POP&SUI groups were significantly decreased (p<0.05), however the difference was not statistical different between SUI and POP&SUI groups (p>0.05). In POP and POP&SUI groups, the NPY expression in the cardinal ligament of uterus, uterosacral ligament, and anterior vaginal wall were negatively correlated with age (p<0.05), however, was not correlated with number of pregnancy, number of delivery, and BMI (p>0.05). CONCLUSIONS: NPY expression was reduced in the round ligament, cardinal ligament of uterus, Uterosacral ligament, and vaginal anterior wall of the patients with POP and SUI. The decreased NPY expression may play an important role in the development of pelvic floordysfunction.