Effects of sex hormones on cell proliferation and apoptosis in the urinary bladder muscle of ovariectomized rat.
OBJECTIVE
To reveal the exogenous effects of sex hormones on cell proliferation and apoptosis in the detrusor muscle of ovariectomized rat urinary bladder.


METHODS
Proliferating cell nuclear antigen (PCNA) and in-situ apoptosis detection kit were used to evaluate cell proliferation and death in the detrusor muscle of castrated female rats after 1 day, 3 days, and 7 days of supplementary sex steroid hormone administration, including estrogen, progesterone, and testosterone. The percentage of cells positive for PCNA (proliferative index) and for apoptosis (apoptotic index) in various groups was calculated.


RESULTS
When compared to the group of bilateral ovariectomy without hormonal supplementation, the groups given 3 days and 7 days of estrogen supplementation (p = 0.031 and p = 0.005, respectively) and the group given 7 days of combined supplementation with estrogen and progesterone (p = 0.044) had a significant increase in the proliferative indices. A significant decrease of apoptotic index was found in the group given 7 days of estrogen supplementation when compared to bilateral ovariectomy without hormonal supplementation (p = 0.035).


CONCLUSIONS
Exogenous estrogen supplementation stimulates proliferation and slows down apoptosis in the detrusor muscle of ovariectomized rat urinary bladder, an effect not counteracted by concomitant use of progesterone. Our results may have clinical implications for estrogen supplementation in offering benefits to menopausal women with lower urinary tract syndromes, based on evaluating the relationship between cell apoptosis and cell proliferation.
Department of Obstetrics and Gynecology, Chang Gung Memorial Hospital, Linkou Medical Center, Taoyuan, Taiwan; College of Medicine, Chang Gung University, Kweishan, Taoyuan, Taiwan. Electronic address: ccjoliang@cgmh.org.tw.
Ching-Chung
CC
Liang
Tsong-Hai
TH
Lee
Shuenn-Dhy
SD
Chang
D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D049109:Cell Proliferation / Q000187:drug effects; D004195:Disease Models, Animal; D004967:Estrogens / Q000494:pharmacology*; D005260:Female; D020249:Hormone Replacement Therapy / Q000379:methods; D059411:Lower Urinary Tract Symptoms / Q000209:etiology / Q000517:prevention & control*; D009130:Muscle, Smooth / Q000166:cytology / Q000187:drug effects; D010052:Ovariectomy / Q000009:adverse effects*; D011374:Progesterone / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D001743:Urinary Bladder / Q000166:cytology / Q000187:drug effects*
D004967:Estrogens; D011374:Progesterone
apoptosis; proliferation; rat; sex hormone; urinary bladder