Ischemic Postconditioning Attenuates Bilateral Renal Ischemia-Induced Cognitive Impairments

Background and aim: Acute kidney injury (AKI) is a frequent complication of kidney failure with high mortality which leads to brain dysfunction. The aim of this study was to investigate the possible protective effect of ischemic postconditioning (IPo) against brain dysfunction induced by bilateral renal ischemia (BRI). Materials and methods: Male Wistar rats underwent BRI, sham or IPo surgery 24h and 1w after reperfusion. Explorative behaviors and motor function of the rats was evaluated by open field, rotarod and wire grip tests. The cognitive function was assessed by passive avoidance learning and Morris water maze tests. Western blotting was performed to assess hippocampal brain derived neurotrophic factor (BDNF) expression. Results: Impairment of balance function induced by BRI was not reversed but Passive avoidance learning impairment was reversed by postconditioning 24h after reperfusion. IPo increased muscle strength compared to BRI group, but explorative behaviors and balance function had no difference 1w after reperfusion. BRI decreased significantly the BDNF protein expression in the hippocampus and postconditioning increased that 24h after reperfusion. Conclusion: Results demonstrated deleterious effect of BRI on cognitive and balance function 24h after reperfusion. IPo showed curative effect against cognitive dysfunction probably through enhancement of BDNF protein expression in the hippocampus.