Hemorrhagic transformation induced by mechanical reperfusion and acute hyperglycemia in a rat ischemic model

Abstract

Objective To investigate an ideal animal model for hemorrhagic transformation(HT) after mechanical thrombectomy for acute ischemic stroke with large-vessel occlusion. Methods Hemorrhagic transformation was examined by 5 h transient middle cerebral artery occlusion and 19 h reperfusion combined with hyperglycemia induced by injection of 50% glucose. Results We found that 80% animals in the experimental group had HT in the basal ganglia and cerebral cortex.Most of HT was the kind of parenchymal hematoma.HT occurred more frequently in the group of multiple injection of high glucose than in the group of single injection of high glucose[88. 5%(23/26)vs.25. 0%(1/4),P< 0. 05].Blood-brain barrier permeability was increased in the ischemic-reperfusion hemisphere.The expression of matrix metalloproteinase-9 was increased in the ipsilateral hemisphere(0. 65±0. 06 vs.0. 37±0. 13,P<0. 01),and that of collagen typeⅣdecreased(0. 48±0. 10 vs.0. 84±0. 08,P<0. 01). Conclusion HT following endovascular mechanical thrombectomy can be successfully simulated by transient middle cerebral artery occlusion for 5 h combined with hyperglycemia induced by multiple injection of high glucose in rats. Key words: Hyperglycemia; Middle cerebral artery infarction