[Effects of "warmth-producing needling for removing obstruction" on hippocampal morphological changes and learning-memory abilities in vascular dementia rats].

OBJECTIVE

To observe the effects of "Warmth-producing Needling for Removing Obstruction" (WPNRO) on the pathomorphological changes of brain and learning-memory abilities in vascular dementia (VD) rats.

METHODS

A total of 50 Wistar rats were randomly divided into normal control, model, medication, needle-twirling, and WPNRO groups, with 10 cases in each group. VD model was established by repeated cerebral ischemia-reperfusion via repeated occlusion of the bilateral common carotid arteries under anesthesia (3% embutal 40 mg/kg, i.p.). "Dazhui" (GV 14), "Baihui"(GV 20) and "Shuigou"(GV 26) were punctured with filiform needles and stimulated with twirling technique and WPNRO technique respectively and continuously for 1 min. Animals of medication group were fed with Nimodipine (0.0108 g/kg). The treatment was conducted once daily continuously for 15 days. The rats' learning and memory results were detected respectively with step-down avoidance test in the first 6 days' training and 24 h later. At the end of experiments and after decapitation, the right brain was taken, cut into sections (5 microm) and stained with H & E method for observing structural changes of hippocampus.

RESULTS

1. Behavior reactions: compared with control group, the latency for finding the safe platform and the times of error in model group increased significantly, and compared with model group, both latencies and times of error in WPNRO, needle-twirling and medication groups decreased considerably (P < 0.05, 0.01). In comparison with needle-twirling group, both latencies and times of error in WPNRO group were significantly fewer (P < 0.05, 0.01), and no significant differences were found between WPNRO and medication groups in these two indexes (P > 0.05). It indicated that acupuncture particularly WPNRO could improve both learning and memory abilities in VD rats. 2) Structural changes of neurons in CA1 region of hippocampus: in normal group, the neurons arranged in order and closely, and were normal in the structure; in model group, the neurons arranged obviously in disorder, had karyopyknosis and hyperplasia in glial cells and decreased in the number. In WPNRO group, no evident cellular karyopyknosis or hyperplasia of glial cells was found, and the structure and number of cells were close to those of normal group. In acupuncture and medication groups, fewer neurons, cellular karyopyknosis and hyperplasia of more glial cells were found.

CONCLUSION

"Warming-producing Needling for Removing Obstruction" can significantly relieve cerebral ischemia induced disturbance of learning and memory and lessen structural injury of hippocampal neurons in rats.