光化学大鼠大脑中动脉血栓形成模型的改进

Photochemical Thrombosis of Middle Cerebral Artery in Rats: A Modified Model

目的 改进光化学大鼠大脑中动脉 (MCA)血栓形成模型 ,使之更适于脑梗死的溶栓治疗研究。材料与方法 经雄性Wistar大鼠股静脉缓慢注入 12 .5mg/kg体重血卟啉衍生物的同时 ,用波长 6 30nm氦 氖激光照射左侧MCA近侧段 15min ,手术显微镜下观察白色血栓形成。然后夹闭双侧颈总动脉 (CCA) 1h开放使其再通。用光镜和电镜观察血栓的特点 ,MRI观察梗死灶。结果 改进后的光化学方法可使MCA被照射段形成闭塞性血小板血栓 ;MCA供血区形成较大的梗死灶且较稳定。结论 改进后的光化学大鼠MCA血栓形成模型仅夹闭双侧CCA 1h后开放 ,使溶栓药物到达血栓部位的途径更接近临床实际 ,并形成较大且稳定的梗死灶。因其造价低廉 ,故更适于脑梗死的溶栓研究。

Objective To improve the photochemical thrombosis model of middle cerebral artery (MCA) in rats, to make the model more suitable for the research of acute cerebral infarction.Materials and Methods Hematoporphyrin derivative (HPD), a photosensitizing dye, was injected into male Wistar rat via the femoral vein (12.5mg/kg), while He-Ne laser with 630 nm wavelength was focused on the proximal segment of MCA for 15 minutes. When white thrombus was seen under an operation microscope, bilateral common carotid artery (CCA) were occluded with an artery clip for 60 minutes, then removed the clip. The features of the thrombus were observed under both light and electronic microscope. The MRI manifestation of the infarcted area was also observed.Results The occlusive platelet thrombus could be seen in the projected segment of MCA. The infarcted lesion in MCA area was large and stable.Conclusion Using modified procedure, the preparation of photochemical MCA thrombosis model in rats needs only 60 minutes to occlude bilateral CCA, thus, the thrombolytic agents can reach the thrombus via the similar route as used in clinical practice. This procedure is rather economic and can produce large and stable infarcted area, thus, it is very suitable for the thrombolytic research in acute cerebral infarction.