Beta‐3 adrenoceptor expression in the uterosacral ligament in the postmenopausal women with pelvic organ prolapse

Abstract

β3-adrenoceptor (β3-AR) agonist is known to relax the detrusor muscles. Considering that both pelvic organ prolapse (POP) and overactive-bladder (OAB) are frequently seen in the elderly population, the effect of β3-AR agonist on the pelvic floor tissues should be investigated. As a first step, this pilot, experimental, and descriptive study was designed to investigate the presence of β3-AR expression in the uterosacral-ligaments (USLs) in postmenopausal (PMP) women with POP. After informed consent, PMP women undergoing hysterectomy for POP were recruited for the intraoperative collection of distal USL between 5/2016 and 8/2016. H&E analysis for the USLs and immunohistochemistry (IHC) analysis for β3-AR and α-actin smooth muscle (SM) were carried out. Tissue composition and percentage of β3-AR expression in the USLs were subjectively measured and the staining results were expressed as descriptive analysis. Total 11 USL specimens were collected and nine specimens were included for the final analysis (one specimen: used for antibody concentration adjustment and one specimen: failed proper staining). Under high-power-field, the USLs were composed of SM cells (81.5 ± 7.47%) and connective tissues (16.5 ± 7.9%). On IHC analysis, six out of nine specimens expressed β3-AR with a different level of expression in SM cells in the USLs. The majority of distal USLs were composed of SM cells. β3-ARs are expressed in 67% of the study specimens. Considering that both POP and OAB are frequently seen in the elderly population, the effect of β3-AR agonist on the pelvic floor tissues should be investigated further.