Temporal diabetes and diuresis-induced alteration of nerves and vasculature of the urinary bladder in the rat.

OBJECTIVE

• To characterize the temporal changes of the nerves and vasculature of the bladder in diabetic rats.

MATERIALS AND METHODS

• A total of 36 Sprague-Dawley rats were divided into three groups: streptozotocin-induced diabetics, 5% sucrose-induced diuretics and age-matched controls. • The characteristics of the nerves and vasculature in the equatorial cross-sectional areas of the bladder were examined by immunofluorescence staining of their specific markers, neurofilament 200 (NF200) and CD31, at 1, 9 or 20 weeks after induction. • The distributions of the nerves and blood vessels were observed and the densities were quantified.

RESULTS

• Diabetes caused a significant reduction in body weight. Bladder weight increased in diabetic and diuretic rats, but not in controls. • The total cross-sectional wall area and detrusor muscle area at the equatorial midline were greater in bladders of diabetic and diuretic rats than in controls. • Neurofilament 200-immunoreactive (NF200-IR) nerves were mainly distributed in the detrusor muscle. CD31-immunoreactive blood vessels were mainly distributed in the mucosa/submucosa. • There were no significant differences in the NF200-IR nerve terminal area among control, diabetic and diuretic groups. However nerve density was decreased at 9 and 20 weeks in the muscle, and at 20 weeks in the mucosa/submucosa in diabetic and diuretic animals. • Blood vessel density decreased in the diabetic and diuretic groups at 20 weeks in the muscle.

CONCLUSIONS

• Diabetes induced time-dependent changes in the density of the nerves and vasculature in the bladder tissues. • Diabetes-related polyuria plays an important role in these changes.