Abstract
Context: One of the main events associated with ischemia/reperfusion injury (IRI) is
excessive production of reactive oxygen species (ROS). Zinc (Zn) and estradiol are
considered as antioxidants that scavenge free radicals.
Objectives: The aim of this study was to compare the protective effect of Zn and estradiol
against renal IRI in ovariectomized rats.
Materials and Methods: Ovariectomized Wistar rats were randomly divided into five
experimental groups including control (sham operated), IRI, estradiol treated +IRI,
estradiol and Zn treated +IRI, Zn treated +IRI groups. The IRI was induced by clamping
renal vessels for 45 minutes followed by 24 hours reperfusion. During the last 6 hours of
reperfusion, urine output was collected and the measurements were performed.
Results: IRI caused an increase in kidney tissue damage score (KTDS) significantly
(P<0.05). The serum levels of blood urea nitrogen (BUN) and the creatinine (Cr) also
elevated by IRI, but theses parameters attenuated by Zn treatment significantly (P<0.05).
Cr-clearance and urine flow were increased by Zn, and the percent of sodium excretion was
increased by estradiol significantly (P<0.05). The kidney tissue level of malondialdehyde
was decreased by co-treatment of Zn and estradiol statistically (P<0.05).
Conclusions: Zn protected the kidney against IRI with an evident improvements of serum
BUN and Cr levels, Cr clearance and tissue damage.