A model of focal cerebral infarction in rat for the study of neural stem cells transplantation

Objective To develop a stable modal of focal cerebral infarction in rats for study of neural stem cells transplantation. Methods Forty-eight rats were assigned into four groups randomly(twelve rats in each group).Different operations were performed in each group: sham operation((group 1)),ligation of the left middle cerebral artery(MCA)(group 2),ligation of the left MCA and the ipsilateral common carotid arteries(CCA)(group 3),ligation of the left MCA and the ipsilateral CCA followed by the temporary clip occlusion of the contralateral CCA for 1.5 hours(group 4).The models was evaluated by neurological deficits,ink perfusion,TTC staining and MRI.(Results) All rats were in good condition after the operation without mortality for 4 weeks.The neurological deficits showed significant difference by analysis of variance(F =19.161,P 0.01).No cerebral necrotic lesions showed in group 1 and group 2 by ink perfusion,TTC staining and MR imaging.Small and unstable necrosis((18 ± 10)mm~3) was found in group 3.In group 4,the necrotic area was confined in the cortex,confirmed by ink perfusion and TTC staining.The areas of infarction were(85 ± 7)mm~3 by MRI 4 weeks later which was different from that of group 3(t=15.545,P 0.01). Conclusion Ligation of the MCA and the ipsilateral CCA followed by the temporary clip occlusion of the contralateral CCA may create a stable model of focal cerebral infarction.Because of its homogeneity of infarction volume and site,and low mortality,it could be used for the study on transplantation of neural stem cells.