Abstract: Objective: To investigate the expressions of Galectin-3 and matrix metalloproteinase-9(MMP-9) in brain tissue of the mice with acute cerebral infarction and the intervention effect of nimodipine,and to elucidate the effects of Galectin-3 and MMP-9 in the occurrence and treatment of cerebral infarction. Methods: A total of 210 mice were randomly divided into control group, model group and nimodipine group (n=70).In model group and nimodipine group, the acute cerebral infarction models of mice were established by the suture method.The mice in nimodipine group were intraperitoneally injected with nimodipine 30 min before operation.The Longar score and modified neurological severity score (mNSS) were used to evaluate the neurological function of the mice in various groups,the cerebral infarction volumes of the mice in various groups were determined by TTC staining,the water contents in brain tissue of the mice in various groups were detected, HE staining was used to observe the morphology of brain tissue of the mice in various groups, the expression levels of Galectin-3 and MMP-9 mRNA in brain tissue of the mice in various groups were detected by RT-PCR method,and the expression levels of Galectin-3 and MMP-9 proteins in brain tissue of the mice in various groups were detected by immunohistochemical staining. Results: Compared with control group, the Longar score and mNSS of the mice in model group were increased(P<0.05),the cerebral infarction volume and water content in brain tissue of the mice in model group were significantly increased(P<0.05), the expression levels of Galectin-3 and MMP-9 mRNA in brain tissue were increased(P<0.05),and the expression levels of Galectin-3 and MMP-9 proteins in brain tissue were increased(P<0.05).Compared with model group, the Longar score and mNSS of the mice in nimodipine group were decreased (P<0.05),the cerebral infarction volume and the water content in brain tissue were decreased(P<0.05),the expression levels of Galectin-3 and MMP-9 mRNA in brain tissue were decreased(P<0.05), and the expression levels of Galectin-3 and MMP-9 proteins were decreased(P<0.05).The morphology and structure of brain cells of the mice in control group were normal;the brain cells of the mice in model group showed edema and flaky necrosis, and the inflammatory cell infiltration was found; the brain cells of the mice in nimodipine group showed mild edema and necrosis. Conclusion: Nimodipine can protect the brain tissue of the mice with cerebral infarction by reducing the expressions of Galectin-3 and MMP-9.

Key words: Galectin-3, matrix metalloproteinase 9, cerebral infarction, nimodipine