Abstract

To explore the effect of Xingnaojing on the somatostain and arginine vasopressin in a rat vascular dementia model, a total of 24 male Sprague-Dawley rats were randomly divided into three groups: sham group (S), vascular dementia group (VD) and Xingnaojing group (XNJ). The memory was measured by Morris water maze test before operation and before and after Xingnaojing treatment. Treatment was performed for 15 days, and then rats were sacrificed. The contents of somatostain (SS) and arginine vasopressin (AVP) in different brain regions (frontal cortex, temporal lobe, hippocampus, cerebral ganglion and corpora striatum) were determined by radioimmunoassay. When compared with S and XNJ groups, the escape latency was significantly prolonged and the platform crossing dramatically decreased in the VD group (P < 0.01); and the SS content was predominantly decreased in frontal area cortex, temporal lobe, hippocampus, cerebral ganglion and corpora striatum (P < 0.01). The AVP content was reduced, but significant difference was only found in the temporal lobe and corpora striatum (P < 0.05). The abnormal learning and memory in VD animals may be attributed to the decrease of SS and AVP after multiple cerebral infractions. Xingnaojing can predominantly raise the contents of SS and AVP in the brain of VD rats, and consequently improve the spontaneous activity and the ability of learning and memory. Xingnaojing injection should be sealed from light, in ampoule bottles, 10 ml each, and this product is an aromatic drug, used immediately after opening, to prevent evaporation.

Key words: Vascular dementia, rat, memory, somatostain, arginine vasopression.