电刺激小脑顶核防治血管性痴呆的实验研究

The prophylactic and curative effects of electrical stimulation of cerebellar fastigial nucleus on vascular dementia in rats

目的 探讨电刺激小脑顶核 (FNS)对血管性痴呆 (VD)的防治作用。方法 采用反复低血压和双侧颈总动脉阻断法建立VD大鼠模型 ,双侧小脑顶核植入电极进行FNS ,用跳台试验、程控穿梭箱试验和神经病理学检查评价FNS对VD大鼠的防治效果。结果 反复全脑缺血前 2d给予FNS 1次或缺血后即刻给予FNS治疗 7d均可明显减轻脑缺血后 2周大鼠的学习和记忆障碍 (P <0 .0 1) ,并使脑缺血后大脑皮层和海马神经元丢失显著减少 (P <0 .0 1)。脑缺血 11周后给予FNS治疗 7d ,虽不能减轻脑缺血后大脑皮层和海马神经元的丢失P >0 .0 5 ) ,但可明显改善大鼠的学习和记忆障碍 (P <0 .0 5 )。结论 FNS对VD大鼠具有明确的防治效果 ,但减轻缺血神经元损害可能只是其防治作用的机制之一。

Objective To investigate the effects of prevention and treatment of cerebellar fastigial nucleus electrical stimulation(FNS) on vascular dementia(VD). Methods The animal model of VD was induced by repeated occlusion of both common carotid arteries in combination with hypotension (40～50 mmHg) in rats. The electrodes were implanted into bilateral fastigial nucleus.The effects of FNS on VD were assessed by step down test,computerized shuttle case test and neuropathological examination.Results FNS significantly improved the disorder of learning and memory at 2 weeks ( P < 0.01 ) or 12 weeks ( P < 0.05 ) of recirculation following repetitive global ischemia in rats, when it was given once 2 day before the ischemic insult and once a day for seven days immediately or 11 weeks after the ischemic insule. FNS also significantly reduced the neuronal cell loss in neocortex and hippocampus(CA 1 throughout CA 4)( P < 0.01 ),when it was given before or immediately after the ischemic insult.Conclusions FNS is evidently benefit to the prevention and treatment of VD in rats, but mitigation of ischemic neuronal injury may be only one of its mechanisms.