Correlation between aquaporins mRNA expression and renal parenchyma thickness in congenital hydronephrotic kidney in children

Abstract

Objective To investigate the relationship between aquaporin-1, -2, -3, -4 mRNA (AQP1-4) and renal parenchyma thickness in congenital hydronephrotic kidney in children. Methods The expressions of aquaporin 1, -2, -3, and -4 mRNA in hydronephrotic kidney of 37 children (aged 60.3±48.8 months) were evaluated with congenital hydronephrosis and control kidney of 6 children (aged 62.7±17.1 months) by using semi-quantitative reverse transcriptase polymerase chain reaction technique. Hydronephrotic kidney parenchyma thickness was measured by B-Ultrasound preoperative-ly and verified at operation. The relations of aquaporin 1, -2, -3, and -4 mRNA to the hydronephrotic kidney parenchyma thickness were analyzed by correlation analysis. Results The aquaporin 1 ,-2,-3, and -4/beta-actin ratio in the hydronephrotic kidney and normal kidney were 0.39±0.22 vs 0.90± 0.10, 0.42±0.20 vs 0.92±0.09, 0.525±0.22 vs 0.98±0.12, 0.30±0.18 vs 0.74±0.21 respec-tively, and the differences were significant (P<0.01). Hydronephrotic kidney parenchyma thickness measured by D-Ultrasound was 5.01±2.38 mm, which was identical with those measured at opera-tion. Significant correlation was found between the levels of aquaporin 1,-2,-3, and -4 mRNA and hydronephrotic kidney parenchyma thickness (r=0.773, 0.772, 0.557, 0.625, respectively; P< 0.01). Conclusions Significant correlation exists between decreased expressions of aquaporin 1 ,-2, -3, and -4 mRNA and atrophic change of renal parenchyma. This result may provide evidence to ex-plain the mechanism why the thinner renal parenchyma thickness, the weaker renal concentration and dilution function. Key words: Aquaporins; Congenital hydronephrosis