Abstract: Objective:To explore the effects of baicalin on the cognitive function and the expression of vascular endothelial growth factor (VEGF), and endostatin(ES) in the brain tissue of the cerebral small vessel disease model rats, and to clarify their mechanisms. Methods:The rat models of cerebellar small vessel disease were duplicated by in vitro implantation of allogeneic microemboli. After successfully modeling, 48 model rats were randomly divided into model group, low dose(50 mg·kg^-1) of baicalin group, and high dose (100 mg·kg^-1) of baicalin group(n=16);On and the sham operation rats were used as control group(n=16).On the first day after modeling, the rats in each group were given drugs,and the learning and memory function of the rats in various groups were detected by Morris water maze experiment at 7, 14, and 28 d after modeling, respectively. The expression levels of VEGF and ES mRNA and protein in the brain tissue of the rats in various groups were detected by RT-PCR and Western blotting methods, and the morphology of the hippocampus tissue of the brain of the rats in various groups were observed by HE staining; the expressions of VEGF and ES proteins in the hippocampus tissue of the brain of the rats in various groups were detected by immunohistochemistry. Results:Compared with control group, the escape latency in Morris water maze of the rats in model group was significantly prolonged(P<0.01), the number of crossing the platform was significantly reduced (P<0.01), the brain tissue lesion was severe, the expression levels of VEGF mRNA and protein in brain tissue were significantly decreased (P<0.01), and the expression levels of ES mRNA and protein were significantly increased (P<0.01). Compared with model group, the escape latency in Morris water maze of the rats in high dose of baicalin group was significantly shortened(P<0.01), the number of crossing the platform was significantly increased(P<0.01), the degree of brain tissue lesion was alleviated, the expression levels of VEGF mRNA and protein in brain tissue were significantly increased(P<0.01), and the expression levels of ES mRNA and protein were significantly decreased (P<0.01). Conclusion:Baicalin can reduce the escape latency, improve the pathological changes, and repaire the cognitive function of brain tissue; it can decrease the VEGF expression level and increase the expression lvels of ES in the brain tissue of the cerebral small vessel disease model rats, and plays a protective role in the brain tissue.

Key words: baicalin, cerebral small vessel disease, vascular endothelial growth factor, erndostatin, cognitive function, morris water maze