Neuroprotective effect of repeated WIN 55,212-2 preconditioning on focal cerebral ischemia-reperfusion injury in rats / 解放军医学杂志

ABSTRACT

Objective To explore the neuroprotective effect of repeated preconditioning with cannabinoid receptor agonist WIN 55,212-2 on focal cerebral ischemia-reperfusion injury in rats.Methods Focal cerebral ischemia was induced by middle cerebral artery occlusion(MCAO)for 120min.Fifty male SD rats were randomly assigned to five groups(10 each)rats in control group and dimethyl sulphoxide group(DMSO group)were intraperitoneally administered 0.3ml normal saline and 0.3ml DMSO once a day for 5 days.Rats in WIN 55,212-2 preconditioning groups(including WIN1,WIN3 and WIN5 group)received intraperitoneal injection of 1mg/kg WIN 55,212-2(dissolved with 0.3ml DMSO)once a day for 1d,3d and 5d,respectively.All animals underwent MCAO operation 24h after last pretreatment to reproduce temporal(120min)focal cerebral ischemia model.The neurological function score(NFS)was evaluated at 24,48 and 72h after reperfusion.Brain infarct was identified with 2% 2,3,5-triphenyltetrazolium chloride(TTC)staining 72h after reperfusion,and the brain infarct volume was expressed as percentage of normal cerebral hemisphere volume.Results The NFSs of rats in WIN 55,212-2 preconditioning groups(WIN1,WIN3 and WIN5 group)were significantly higher,and the infarct volumes were significantly smaller than that in control group and DMSO group at 24h,48h and 72h after reperfusion(P0.05).Conclusion The neuroprotective effect of repeated preconditioning with cannabinoid receptor agonist WIN 55,212-2 may be enhanced by increased time of pretreatment.