Renal anomalies in the VATER animal model.

BACKGROUND PURPOSE: Renal anomalies are a prominent feature of the VATER association. Administration of Adriamycin to timed-pregnant rats resulted in a spectrum of anomalies similar to the human VATER association. The aim of this study is to describe the renal anomalies in the Adriamycin animal model.

METHODS

Timed-pregnant Sprague-Dawley rats were injected with Adriamycin intraperitoneally at a dose of 2 mg/kg on days 6 through 9 of gestation. Full-term fetuses were fixed in Bouin's solution and serial transverse sections were analyzed by light microscopy. All specimens were compared with suitable controls.

RESULTS

In experimental animals, renal anomalies were found in 98% of the examined fetuses. Bilateral hydroureteronephrosis with kinking of the ureters was obvious. Ureteric atresia led to obstructive uropathy. Bladder agenesis occurred in all experimental animals. Mesonephric ducts were seen joining a proximally blind-ending urethra in male animals. In females both paramesonephric ducts ended blindly after joining each other, and this resulted in vaginal atresia. In association with imperforate anus, a recto-urethral and a recto-urogenital fistula was seen in male and female fetuses, respectively.

CONCLUSIONS

Bladder agenesis was an important feature in the Adriamycin animal model. Bilateral hydronephrosis resulted from blind-ending ureters.