The Effect of Enalapril on Renal Resistive Index, Urine Electrolyte Levels and TGF-β1 Levels of Kidney Tissues in Rats with Unilateral Partial Ureteropelvic Junction Obstruction

Abstract

Background:

This study aimed to investigate renal arterial resistive index measurements and urine electrolytes before and after enalapril therapy in a rat model of unilateral ureteropelvic obstruction. The transforming growth factor (TGF)-β1 response of the renal tissue was also investigated.

Materials and Methods:

30 Wistar albino rats were randomly allocated into 5 groups (n=6). Group C rats served as controls. Group S rats had only laparotomy. Group E rats were only treated with enalapril. Rats in group UP and group UPE underwent laparotomy to create a left unilateral moderate partial obstruction. 2 weeks after establishing partial ureteropelvic junction obstruction, group UPE rats were treated with enalapril. Urine was collected over 24 h in all groups. Intrarenal arterial resistive index measurements were performed before and 2 weeks after surgery and after enalapril treatment in group UPE, and before and after enalapril treatment in group E. Rats were sacrificed by intracardiac puncture and left kidneys were harvested to evaluate levels of mRNA TGF-β1.

Results:

There was no significant difference in ARI values in group E. In group UPE, the difference between ARI values before and after surgery was statistically significant; the difference between ARI values after surgery and after enalapril treatment was also statistically significant. There was no statistically significant intra-group difference in urine electrolyte levels for UP group or UPE group. There was no difference in renal mRNA TGF-β1 levels.

Conclusion:

Enalapril maintained renal blood flow by decreasing the arterial resistive index and maintained renal tubular function by protecting urine concentration and dilution ability in a rat model with unilateral ureteropelvic junction obstruction.

Key words

ureteropelvic junction obstruction - enalapril - arterial resistive index - urine electrolyte - transforming growth factor – β1

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