50 week ultrasound imaging and ultrastructural abnormalities of bladder after sugar diuresis and diabetes mellitus in rats.

PURPOSE

To investigate 50 week ultrasound imaging and ultrastructure changes of bladder in diuresis and diabetes rats.

METHODS

Forty-two healthy male Sprague-Dawley rats were randomly divided into control group, sugar-induced diuresis group and streptozotocin-induced diabetes group. The 24 h drinking and urine volume were calculated from 21 to 31 weeks. Using ultrasound to assess bladders after 49 weeks. Bladders were examined by transmission electron microscope after 50 weeks.

RESULTS

The drinking and urine volume significantly increased in the diuresis and diabetes groups. The bladder morphology and bladder wall thickness increased in the diuresis and diabetes groups. Bladder stones, bladder overdistension and urinary retention were seen in the diuresis and diabetes groups. Urothelium manifested degeneration, denudation and necrosis in the diuresis and diabetes groups. The mitochondrial vacuolar degeneration in the urothelial cells was seen in the diabetes group. The subepithelial vascular endothelial cells hyperplasia with a narrowed lumen were observed in the diabetes group. Abnormal mitochondria were rarely seen in the control group. The mitochondrial vacuolar degeneration in the detrusor was more severe in the diabetes group than in the diuresis group. The detrusor muscle and axon degeneration were observed in the diuresis and diabetes groups. Two rats in the diuresis group share similarities with diabetes group (2/6).

CONCLUSION

Long-term diabetes mellitus can cause increments of urinary bladder morphology and bladder wall thickness, urinary retention and bladder stones. Ultrastructural degeneration of the bladder might be the morphological bases of diabetic cystopathy.