RESUMO
OBJECTIVE: To observe the effect of catgut embedment at "Baihui" (GV 20), "Dazhui" (GV 14), etc. on learning-memory ability, expression of hippocampal protein kinase C interacting protein 1 (PICK 1) and glutamate receptor 2 (GluR 2) proteins and level of calcium ions, so as to explore its mechanism underlying improvement of vascular cognitive impairment. METHODS: A total of 56 male SD rats were randomly divided into sham operation, model, catgut embedment and medication groups (n=14 in each). The chronic ischemic cognitive impairment model was established by permanent occlusion of bilate-ral common carotid arteries. The catgut embedment was applied to GV 20, GV 14, "Shenshu" (BL 23) and "Xuanzhong" (GB 39), once a week, for 4 weeks. Rats of the medication group received intraperitoneal injection of monosialate tetrahexose ganglioside sodium (GM-1, 0.33 mg/kg), once daily for 4 weeks. The rats' learning-memory ability was detected by Morris water maze tasks, pathological changes of hippocampal Nissl's bodies were tested by Nissl staining. The expression levels of PICK 1 and GluR 2 proteins in the hippocampus were detected by Western bolt (WB), and the concentration of calcium ions in the hippocampus tissue was measured by Bicinchoninic acid (BCA) assay. RESULTS: After modeling, the mean escape latencies of place navigation test were significantly increased while the crossing times of target platform quadrant of space probing test notably decreased in the model, catgut embedment and medication groups compared with their own individual pre-modeling (P0.05). CONCLUSION: Catgut implantation at GV 20 etc. can effectively improve the learning-memory ability in rats with chronic ischemic cognitive impairment, which may be related to its effects in down-regulating the expression of PICK 1 and calcium ion concentration and up-regulating the expression of AMPA receptor subunit GluR 2 protein in the hippocampus.