Abstract
Background
Renal aquaporins (AQP1-4) concentration is downregulated and is in proportion to the degree of hydronephrosis graded by ultrasound in pediatric congenital hydronephrosis (CH). However, the relationship between the expression of AQP1-4 with the changes of renal function impairment (RFI) evaluated by 99mTc-DTPA renal dynamic imaging is still unclear. This study aimed to investigate the relationship between AQP1-4 expression and degree of RFI in children with CH.
Methods
The expression of AQP1-4 was evaluated in 45 children with unilateral ureteropelvic junction obstruction (28 boys and 17 girls, average age: 28±10 months) and 15 children undergoing nephrectomy for nephroblastoma (8 boys and 7 girls, average age: 26±8 months) by immunoblotting and immunohistochemistry. Renal function was graded into mild and severe RFI by 99mTc-DTPA renal dynamic imaging.
Results
One-way analysis of variance with Bonferonni’s correction showed a significantly reduced protein expression of AQP1–4 in the severe RFI group compared with those in both mild RFI group and controls (AQP1: 0.52±0.09 vs. 0.91±0.06 vs. 1.23±0.033; AQP2: 0.68±0.12 vs. 1.09±0.06 vs. 1.52±0.08; AQP3: 0.59±0.16 vs. 0.94±0.08 vs. 1.31±0.07; AQP4: 0.64±0.06 vs. 1.14±0.07 vs. 1.61±0.07; P<0.001, respectively). In kidneys with severe RFI, there was a reduction in the protein concentration of all four AQP isoforms which was more pronounced compared with those seen in kidneys with mild RFI and in the controls.
Conclusion
AQP1-4 expression is reduced in proportion with the impairment degree of renal function graded by 99mTc-DTPA renal dynamic imaging in human CH.
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Li, ZZ., Xing, L., Zhao, ZZ. et al. Decrease of renal aquaporins 1–4 is associated with renal function impairment in pediatric congenital hydronephrosis. World J Pediatr 8, 335–341 (2012). https://doi.org/10.1007/s12519-012-0378-9
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DOI: https://doi.org/10.1007/s12519-012-0378-9