Improving effect of Tujia Medicine Tianzhusan on learning and memory impairment caused by cerebral ischemia / 中草药

ABSTRACT

Objective: To investigate the therapeutic effects of Tianzhusan (TZS) on the related indexes of learning and memory impairment of rats with vascular dementia (VD) caused by cerebral ischemia. Methods: The rats' models were prepared by a permanent ligation of the bilateral common carotid arteries. After ig administration for 63 d, the learning and memory abilities of rats were observed with Morris water maze, the pathological changes in hippocampus were detected with HE staining and Nissl staining, and the expression levels of microtubule associated protein-2 (MAP-2) and synaptophysin-1 (SYN-1) in hippocampus were evaluated by immunohistochemistry. Results: The latent period of rats in the model group was longer than that in the control group obviously (P < 0.05). However, the latent period of rats in Nimodipine and TZS groups was shortened after ig administration by different degrees. HE staining showed that the neuronal cells appeared necrosis and deformation in CA1 and CA3 areas of hippocampus of rats in the model group, while Nimodipine and TZS could reduce these injuries. Nissl staining showed that TZS could increase the number of Nissl bodies in CA1 and CA3 areas of hippocampus. Nimodipine and TZS could improve the expression level of MAP-2 in hippocampus. The rats in the model group had a high expression of SYN-1 in CA1 and dentate gyrus areas, but a low expression in CA3 area. Nevertheless, TZS could increase the expression of SYN-1 in CA3 area. Conclusion: TZS could improve the learning and memory abilities of VD rats by relieving the damage of neuronal cell, promoting the synthesis of neurotransmitters, and regulating the expression levels of MAP-2 and SYN-1.