phytoestrogens and Urinary-Bladder--Overactive

Development of urinary incontinence, for many women, occurs following menopause. Dietary phytoestrogens consumed over the long term may affect the contractile function and maintenance of the urinary bladder in post menopausal women. This study examined the muscarinic receptor mediated contractile responses in the rat isolated bladder in response to ovariectomy and long term dietary phytoestrogen consumption.. Ovariectomised or sham-operated female Wistar rats (8 weeks) were fed either normal rat chow (soy, phytoestrogens) or a non-soy (phytoestrogen free) diet. Bladders were dissected from rats at 12, 24 and 52 weeks of age and placed in 25 ml organ baths filled with McEwans solution.. The contractile response to carbachol, in 12 week old female rats did not change as a result of dietary phytoestrogens or ovariectomy (P>0.05). At 24 weeks of age, detrusor muscle strip responses to carbachol from non-soy fed ovariectomised rats were attenuated (P<0.05). At 52 weeks, bladder detrusor strip responses to carbachol were reduced in all treatment groups with the exception of the soy-fed sham operated rats.. These results suggest an age-related reduction in the contractile response of the detrusor to the muscarinic receptor agonist carbachol, which may be prevented by long term dietary phytoestrogen intake.

Topics: Age Factors; Animal Feed; Animals; Body Weight; Carbachol; Cholinergic Agonists; Female; Glycine max; In Vitro Techniques; Muscle Contraction; Muscle, Smooth; Organ Size; Ovariectomy; Phytoestrogens; Rats; Rats, Wistar; Receptors, Muscarinic; Soybean Proteins; Urinary Bladder; Urinary Bladder, Overactive