目的 研究注射用腦蛋白水解物（Ι）對血管性癡呆大鼠的保護作用。方法 采用改良兩血管阻斷法制備血管性癡呆（VaD）大鼠模型，假手術(shù)組分離頸總動脈后縫合切口。模型大鼠隨機分為模型組，腦蛋白水解物注射液（Cerebrolysin，陽性藥，10 mg/kg）組，注射用腦蛋白水解物（Ι）高、中、低劑量（20、10、5 mg/kg）組，尾iv給藥，每天1次，連續(xù)給藥2周；假手術(shù)組給予等體積生理鹽水。采用Y迷宮和避暗實驗法評價大鼠學(xué)習(xí)記憶能力；ELISA法檢測VaD大鼠血清中胰島素樣生長因子1（IGF-1）水平。結(jié)果 與模型組比較，注射用腦蛋白水解物（Ι）顯著增加VaD大鼠在Y迷宮實驗的正確次數(shù)，顯著降低在避暗實驗的潛伏期時間，并顯著提高VaD大鼠血清IGF-1水平；上述作用與同劑量Cerebrolysin比較無顯著差異。結(jié)論 注射用腦蛋白水解物（Ι）能提高VaD大鼠學(xué)習(xí)記憶能力，其機制可能與提高機體IGF-1水平，促進腦損傷后的神經(jīng)元修復(fù)和生長有關(guān)。

Objective To investigate the protective effects of Cerebroprotein Hydrolysate for injection (Ι) on vascular dementia (VaD) in rats.Method The permanent bilateral common carotid artery ligation method was used to prepare a VaD rat model. Suture of rats was performed after separation of the common carotid artery in Sham group. The model rats were randomly divided into model group, Cerebroprotein Hydrolysate Injection (Cerebrolysin, 10 mg/kg, positive drug group), Cerebroprotein Hydrolysate for injection (I) high, medium and low dose (20, 10 and 5 mg/kg) groups. Rats were treated with relative drug by tail iv injection once daily for two weeks, and rats in Sham group were given equal volume of saline. The learning and memory abilities were evaluated by Y maze and step-through tests. Besides, the levels of insulin-like growth factor-I (IGF-1) in VaD rat serum were determined by ELISA method.Results Compared with model group, Cerebroprotein Hydrolysate for injection (Ι) significantly increased the correct number in Y maze test, reduced the step-through latency time, and elevated serum IGF-1 level in VaD rats. The protective effects of Cerebroprotein Hydrolysate for injection (Ι) in VaD rats were equivalent to the same dose of Cerebrolysin.Conclusion Cerebroprotein Hydrolysate for injection (Ι) could significantly improve the learning and memory abilities of VaD rats, presumably through a mechanism of elevating IGF-1 level, which promotes the repairment and growth of neurons.