The effects of estrogen on passive avoidance memory impairment induced by acute kidney injury in ovariectomized rats

Abstract

Background: The aim of this study was to evaluate the effects of acute kidney injury (AKI) and mediatory role of the estrogen on passive avoidance memory in ovariectomized rats. Methods: Frothy ovariectomized Wistar rats were subjected to sham-vehicle, sham-estrogen, renal ischemia reperfusion (RIR)-vehicle, and RIR-estrogen groups. AKI was induced by ischemia reperfusion. Estrogen (200 µg/kg in 0.2 ml/100 g body weight) was injected subcutaneously once a week for four weeks. Then, passive avoidance memory was assessed. Findings: AKI resulted a significant decrease in the mean latency of entering the dark chamber (P < 0.010). Although, estrogen therapy following AKI led to elevated blood urea nitrogen (BUN) and creatinine, but, there was no significant difference in the delay in entering the dark chamber in RIR-estrogen group compared to RIR-vehicle group (P = 0.100). Conclusion: The results showed that AKI could have a deleterious effect on passive avoidance memory. However, the studied dose of estrogen cannot prevent passive avoidance memory impairment induced by AKI. © 2019, Isfahan University of Medical Sciences(IUMS). All rights reserved.