TGF-BETA MESSENGER-RNA EXPRESSION IN THE RENAL PELVIS AFTER EXPERIMENTAL AND CLINICAL URETEROPELVIC JUNCTION OBSTRUCTION

Purpose: The renal parenchymal expression of transforming growth facto r-beta (TGF-beta) is increased in experimental obstructive uropathy. T o better understand the pathophysiology of hydronephrosis, we pursued this observation by determining if the expression of TGF-beta is also increased in the obstructed renal pelvis. Materials and Methods: The e xpression of TGF-beta mRNA was evaluated in experimental and clinical ureteropelvic junction obstruction by reverse transcriptase polymerase chain reaction (RT-PCR). Southern blot analysis with labeled human cD NA probes for TGF-beta was then done to verify the results. Results: E xperimentally, pelves subjected to ureteral constriction showed signif icantly higher TGF-beta mRNA expression than normals. After reversal o f obstruction, the expression of TGF-beta remained significantly highe r than normals but was not different from pelves with ongoing obstruct ion. Clinically, there was a significantly higher level of TGF-beta mR NA expression in obstructed pelves than in nonobstructed ureters. High levels of TGF-beta mRNA expression correlated significantly with good clinical outcome, good renal function, muscle hypertrophy and acute o nset of obstruction. Conclusions: There is increased TGF-beta mRNA exp ression in the renal pelvis following clinical and experimental ureter opelvic junction obstruction. These data implicate TGF-beta in the ada ptive molecular responses that increase muscle and collagen elaboratio n seen in hydronephrosis.