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Ischemic stroke (Cerebral Ischemic Stroke, CIS) is the limitations of ischemic brain tissue Necrosis or softening of the brain caused by the stenosis or occlusion of intracranial or extracranial arterial, leading to the artery area blood supply to the brain disorder, ischemia, and hypoxia. Cerebral ischemic stroke is most often caused by the narrowing of the arteries due to atherosclerotic plaque and thrombosis.Amount of experimental studies have shown that atherosclerosis mainly affects medium and large arteries in the body, particularly the main brain arteries which is the most important in life and health, thus often causing serious stroke events. Therefore, ischemic stroke due to atherosclerosis are more common in the clinical. The physiological and pathological process of ischemic stroke is more complex and the mechanism is still not very clear.Hypoxia Inducible Factor-1αis a hypoxia response which plays an important role in the transcription factors involved in the pathophysiological process of the body, in the process through various mechanisms of stroke and also plays an important role in the neuroprotective. In recent years, many clinical and animal experiments show [2], HIF-1αis widely distributed in the brain, involved in the process of cerebral ischemia and hypoxia. It regulates anaerobic metabolism by the expression of target genes in the hypoxia, and promotes EPO, VEGF, FGF, TGF-βincreases. So that the hypoxic cells can maintain a certain oxygen concentration and cells can survive in hypoxia. In recent years, studies abroad or in China have shown that HIF-1αis closely related with ischemic stroke, which occurs in the ischemic stroke and plays an important role in the progression of the disease.Currently research in HIF-1αand ischemic stroke always focused on its expression and the development of cerebral ischemia alone, whereas the modeling of atherosclerotic based ischemic stroke and the changing of HIF-1αin the model is in few studies.Objective To investigate the basis of atherosclerosis in cerebral ischemic stroke in a rat model, the model is built to successfully evaluate the morphology, pathology, and the expression of HIF-1αin the rat brain with its significance.Methods 60 healthy adult male wistar rats , in the control group (n = 30) and experimental group (n = 30), prepared on the basis of healthy rat model of ischemic stroke and atherosclerosis in rats with ischemic stroke on the basis of Model. Each group is divided into sham operation, ischemia 0.5,6,12,24 h subgroup. The success of the modeling is determined by the morphology observed under light microscope HE staining and pathophysiology. The changes in expression of HIF-1αmRNA are detected by immunohistochemical expression of HIF-1αprotein and RT-PCR. Measured data are analyzed by image analysis system, which measures the average protein and mRNA expression in optical density, the average gray value. The data are also analyzed by spss17.0 for statistical analysis.Results1. The successfully of the model(1) symbol of success of model of atherosclerosis: HE staining, light microscopy of aortic endothelial discontinuity, plaque formation; calcification; in the smooth muscle hyperplasia, elastic fiber breakage; outer membrane thinning,(2) symbol of success model of ischemic stroke: after the observation of animal behavior and body awakening, global cerebral ischemia mydriasis, conjunctival dark red, arched vertical hair, surgical success.2.Immune staining:0.5h control group and experimental group in the subgroup of ischemic brain tissue HIF-1αexpression has been obvious, 6h, reached the peak sub-group, 12,24 h in the continued high expression subgroup. Statistically significant: experimental group and control group with sham operation subgroup 0.5h sub-group was statistically different (P <0.05). 6h sub-group than in sham, ischemia 0.5h significantly different subgroups (P <0.05). Ischemia 12,24 h subgroups, respectively, compared with 6h subgroup, there is no significant difference statistically (P> 0.05). No significant difference between the experimental group and control group.3. RT-PCR Detection:0.5h control group and experimental group in the subgroup of ischemic brain tissue has been significant HIF-1αmRNA expression, 6h, reached the peak sub-group, 12,24 h in the continued high expression subgroup , Statistically significant: experimental group and control group with sham operation subgroup 0.5h sub-group was statistically different (P <0.05). 6h sub-group than in sham, ischemia 0.5h significantly different subgroups (P <0.05). Ischemia 12, 24 h subgroups, respectively, compared with 6h subgroup no significant difference statistically (P> 0.05). No significant difference between the experimental group and control group.Conclusion: The high fat diet formula and bilateral carotid artery occlusion method can be successfully established on the basis of atherosclerosis in ischemic brain model; the basis of atherosclerosis can be induced ischemic stroke increased expression of HIF-1α, can occur in the expression of early ischemia, and increased with time, 6h peak, suggesting that HIF-1αin atherosclerotic ischemic stroke on the basis of law and the expression of HIF-1αin ischemic stroke alone is of the same pattern.
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