Abstract: Objective: To investigate the protective effect of Shuxuening Injection on the brain tissue of the rats with acute cerebral infarction,and to elucidate its mechanism. Methods: Fifty rats were randomly divided into control group, sham operation group, model group, nimodipine group and Shuxuening Injection group(n=10).The rat models of acute cerebral infarction were made by internal carotid artery suture method in model group, nimodipine group and Shuxuening Injection group. The common carotid arteries, the external carotid arteries and the internal carotid arteries of the rats in sham operation group were separated,and only the external carotid arteries were ligated; the rats in control group were not treated with operation; the rats in Shuxuening Injection group were given Shuxuening Injection, the rats in nimodipine group were given nimodipine,and the rats in control group, model group and sham operation group were given normal saline at the same volume.The score of neurological impairment, water contents in brain tissue and relative cerebral infarction areas of the rats in various groups were measured.HE staining was used to observe the morphology of brain tissue of the rats in various groups,and immumohistochemical staining was used to detect the expression levels of growth differentiation factor -15(GDF-15) and C-reactive protein (CRP) in brain tissue of the rats in various groups. ELISA method was used to detect the levels of tumor necrosis factor-α(TNF-α), interleukin- 6(IL-6)and interleukin-1β(IL-1β)in brain tissue of the rats in various groups. Results: The cortical structures of cortex of the rats in control group and sham operation group were complete and the cells were arranged neatly;the cytoplasm and nucleus of the nerve cells of the rats in model group were wrinkled, and the interstitium between nerve cells and capillaries were loose; the swelling degrees of cerebral cortical nerve cells and glial cells and the loose degrees of stroma of the rats in Shuxuening Injection group were reduced, and the histopathological manifestations were similar to those in nimodipine group. Compared with control group and sham operation group, the water content in brain tissue of the rats in model group was significantly increased(P<0.05), and the expression levels of CRP,the levels of TNF-α, IL-6 and IL-1β in brain tissue of the rats in model group were significantly increased(P<0.05), while the expression level of GDF-15 was significantly decreased(P<0.05).Compared with model group, the scores of neurological impairment of the rats in nimodipine group and Shuxuening Injection group were significantly decreased (P<0.05), and the relative cerebral infarction areas(P<0.05),the water contents in brain tissue(P<0.05),the expression levels of CRP,the levels of TNF-α, IL-6, and IL-1β in brain tissue of the rats in nimodipine group and Shuxuening Injection group were significantly decreased(P<0.05), while the expression levels of GDF-15 were significantly increased(P<0.05).Compared with nimodipin group, the score of neurological impairment,the relative cerebral infarction area, the water content in brain tissue,the expression levels of CRP and GDF-15 and the levels of TNF-α, IL-6 and IL-1β in brain tissue of the rats in Shuxuening Injection group had no statistical significances (P>0.05). Conclusion: Shuxuening Injection can protect the acute cerebral infarction by up-regulating the expression of GDF-15 and inhibiting the expression of CRP in brain tissue of the rats with acute cerebral infarction, reducing the levels of inflammatory cytokines and improving the neurological function.

Key words: cerebral infarction, Shuxuening Injection, brain tissue, growth differentiation factor 15, C-reactive protein