Effect Of Hyperglycemia On Neurocyte Apoptosis And The Expression Of Caspase-12, GRP In Rats With Cerebral Ischemic Reperfusion Injury

Objective:through the study of neurocyte apoptosis and the expression of caspase-12, GRP78in rats with focal cerebral ischemic reperfusion injury in hyperglycemia conditions, to investigate the hyperglycemia aggravate mechanism of cerebral ischemic reperfusion injury.Methods:A total of56male sprague-dawley rats were randomly divided into3groups: sham operation group(n=8) and normal glucose group(n=24), hyperglycemia group(n=24). The hyperglycemia model was made by tail vein injection of25%glucose(4g/kg) and the model of ischemic reperfusion was produced after middle cerebral artery occlusion, and all time point of reperfusion3h,12h,24h after ischemia2h Scored neurological action with Zea-Longa standard, counted the number of apoptotic cells with TUNEL methed, detected expression of caspase-12,caspase-9with immunohistochemistry and GRP78with Western-Bloting method, last analysised image.Results:(1) sham operation group:The scores of neurological deficit was0, the cell apoptotic index of neurons was1.55%±0.83%, caspase-12was0.00±0.00,caspase-9was3.56±1.14, GRP78was0.064±0.004.(2) normal glucose group after in reperfusion12h:The scores of neurological deficit was2.57±0.12, the cell apoptotic index of neurons was12.87%±3.08%, caspase-12was0.63±0.04,caspase-9was24.63±5.85, GRP78was0.267±0.128.(3) hyperglycemia group after in reperfusion12h:The scores of neurological deficit was3.42±0.48, the cell apoptotic index of neurons was19.23%±3.83%, caspase-12was1.03±0.09,caspase-9was36.20±10.27, GRP78was0.197±0.084.comparing with sham operation group, normal glucose group and hyperglycemia group was significant enhanced in neurological action, apoptotic index and the expression of caspase-12and caspase-9, GRP78each time point (P<0.01) comparing with normal glucose group, hyperglycemia group was enhanced in neurological action (P<0.05), and significant enhanced in apoptotic index and the expression of caspase-12and caspase-9(P<0.01) at same time point, but the expression of GRP78in hyperglycemia group was lower (P<0.05)Conclusion:(1) The expression of caspase-12and caspase-9、GRP78may participate in the pathology of the hyperglycemia exaggerated cerebral ischemic reperfusion injury.(2) hyperglycemia could aggraviate ischemia injury by increased the expression of caspase-12and caspase-9.(3) hyperglycemia could aggraviate ischemia injury by decreased the expression of GRP78.