Effects Of KATP Channel Opener On Synaptic Plasticity After Cerebral Infarction

Background and ObjectiveWith population growth and aging,more and more patients with cerebral infarction have varying degrees of disability.The promotion of functional recovery after cerebral infarction has become the focus and challenges of research.Nicorandil is the KATP channel opener,which is widely found in brain regions.In the case of cerebral ischemia and hypoxia,the KATP channel is activated,cell hyperpolarization and cell excitability are reduced,thus generating neuroprotective effects.Some studies have reported that nicorandil play a neuroprotective role in cerebral ischemia by reducing inflammation and apoptosis.However,only a few studies explored its role in synaptogenesis.In this study,we made rat MCAO model and observed postoperative behaviour and the levels of synaptic remolding related factors to verify the experimental results.MethodsSD rats were randomly divided into four groups: Sham group,MCAO group,MCAO+Nicorandil group and MCAO+Vehicle group.We made rat MCAO model.TTC was used to detect the infarct volume,m NSS was used to detect the neurological deficit,and the brain water content was measured to observed cerebral edema.Morris water maze was used to observe the spatial learning and memory of rats.The expressions of Brd U,Neu N,SYP and GAP43 was observed by immunofluorescence.The m RNA expressions of Neu N,SYP and GAP43 were detected by RT-PCR.The protein expressions of Neu N,SYP and GAP43 were detected by Western blot.Results1 Compared with MCAO group and MCAO+Vehicle group,MCAO+Nicorandil group had significantly reduced cerebral infarct volume,brain water content and neurological deficit,and improved learning and memory function.2 Immunofluorescence showed that Brd U expression was significantly increased in the MCAO+Nicorandil group,and the m RNA and protein expression of Neu N were increased compared with those in MCAO group and MCAO+Vehicle group.3 Compared with MCAO group and MCAO+Vehicle group,the m RNA and protein expression of SYP and GAP43 were increased in MCAO+Nicorandil group.ConclusionNicorandil can improve nerve function recovery after cerebral infarction,reduce brain injury and promote synaptic formation.