Isoflavone regulates Vascular Endothelial Growth Factor Expression in urinary tract of castrated rats

Dietary phytoestrogens maintain contractile responses to carbachol with age in the female rat isolated bladder

AIMS

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.

MAIN METHODS

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.

KEY FINDINGS

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.

SIGNIFICANCE

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.

Sexual steroids in urogynecology

The decline in sex hormone levels that accompanies the menopause has substantial effects on the tissues of the urogenital system, leading to atrophic changes. These changes can have negative effects on sexual and urinary function. The authors evaluate the repercussion of hypoestrogenism and sexual steroids on some elements of the pelvic floor and lower urinary tract. They summarize their research work and review significant published papers. They emphasize the changes in urinary mucosae, periurethral vessels, muscular layer, connective tissue, gene expression, autonomic nervous system receptors, as well as the main clinical aspects involved.