Evidence of progesterone receptors in the mucosa of the urinary bladder

Objective: To investigate whether progesterone receptors are present in the mucosa of the urinary bladder of continent premenopausal women compared wi th continent postmenopausal women. Materials and methods: Fifty-seven biopsies from the mucosa of the trigone and lateral wall of the urinary bladder were examined by the avidin-biotin- peroxidase immunohistochemical technique for the presence of estrogen and p rogesterone receptors. The specimens were obtained at cystoscopy performed to investigate hematuria in 42 patients and neoplasia in 15. The study grou p (n = 29) comprised non-pregnant premenopausal women in the luteal phase o f their menstrual cycle and the control group (n = 28) comprised postmenopa usal women. None of the subjects had urinary incontinence or was taking med ication with hormones. In no case did the primary lesion involve the specim en used for laboratory analysis. Results: There was positive immunostaining with estrogen in 28 patients of the study group (96.5%) and 4 (14.4 %) in the control group (p < 0.0001). T he 28 samples of the study group also showed positive immunostaining for pr ogesterone receptors. There was positive immunostaining with progesterone i n 18 samples (64.3%) of the control group (p < 0.01). Fourteen samples (50% ) of the control group thus showed positive immunostaining for progesterone but no evidence of positive immunostaining with estrogen. Immunostaining f or estrogen and progesterone receptors was similar in trigonal and lateral wall samples. Conclusion: In continent pre- and post-menopausal women, a direct progestog enic effect on the mucosa of the urinary bladder seems likely in addition t o estrogen.