Angiotensin II, type 2 receptor in the development of vesico-ureteric reflux

To investigate if mutation of the angiotensin II (Ang II) receptors AT2 is involved in primary vesico-ureteric reflux (VUR) in humans.

Genetic polymorphisms in the AT1 and AT2 receptors was evaluated in 23 patients having the most common congenital urological abnormality, namely primary congenital VUR. The occurrence of the A1166C transition in the AT1 receptor gene and the A-1332G transition in the AT2 receptor gene were evaluated and compared with the incidence in normal controls with no urological abnormalities.

The distribution of the AT1 receptor genotypes was no different between patients with VUR and healthy controls. Furthermore, 10 of 23 (44%) patients with VUR and seven of 19 (42%) controls carried the AT2 receptor gene variation. These results contrast with our previous finding of an association between the A-1332G transition in the AT2 receptor gene and primary obstructive megaureter, and pelvi-ureteric junction obstruction.

We propose that while the AT2 receptor is crucial for the normal development of the ureter, it does not contribute to the processes which culminate in VUR, which is primarily an abnormality in the bladder trigone.