Histological changes following two-step flap gastrocystoplasty in rats.

ABSTRACT

INTRODUCTION: A gastric segment used to increase bladder capacity can undergo considerable changes over time, as can all intestinal segments implanted in the urinary tract and in contact with urine. This experimental study reports the differences between the histological alterations observed in the gastric patch transposed in the bladder both with its own pedicle and after deafferentation from the stomach. MATERIALS AND METHODS: A group of 30 young male Sprague-Dawley rats underwent gastrocystoplasty. Survivors were divided into 3 groups gastrocystoplasty alone (8 rats); gastrocystoplasty with vascular deafferentation at 15 days (7 rats), and at 2 months (8 rats). 5 rats were used as controls. Urinary pH was evaluated during a 6-month follow-up. RESULTS: Histology showed that early devascularization hindered the fusion of the two mucosae in the junctional area but reduced papillary hyperplasia (p = 0.013) of the gastric mucosa. No changes were observed in urinary pH after patch devascularization. CONCLUSIONS: Vascular deafferentation creates a gastric flap on the bladder which, even if it does not prevent urinary acidification, reduces the frequency of histologically detected changes susceptible for transformation into neoplasms.