K-银环蛇毒素对小鼠被动学习和空间记忆的影响

Effects of Kappa Bungarotoxin on Avoidance Learning and Spatial Memory Abilities in Mice

以Ｋ－银环蛇毒素（Ｋ－ＢＧＴ，３．２５μｇ／ｋｇ）海马内注射可造成小鼠胆碱能神经Ｎ受体功能受损的学习记忆的障碍。水迷宫检测结果表明，Ｋ－ＢＧＴ组小鼠空间学习记忆明显下降，训练第４天，逃避潜伏期比第１天下降仅为１６．７％，而对照组逃避潜伏期比第１天下降达５８．３％。在第５天６轮共６０次训练中，对照组在规定时间内找到平台的百分数为８０．０％，而Ｋ－ＢＧＴ组仅为３３．３％。撤去平台后第１天，对照组穿越原平台所在部位的次数为（５．３±２．８）次，而Ｋ－ＢＧＴ仅为（１．９±１．２）次。此外搜寻平台方式构成方面也出现了明显变化。避暗测试结果表明，Ｋ－ＢＧＴ组比对照组潜伏期下降３８．３％，错误率比对照组增加了２．２５倍。卵磷脂４０ｍｇ／ｋｇ经胃灌服１４天对Ｋ－ＢＧＴ所致学习记快损伤具有一定的改善作用。

おおappa bungarotoxin(KBGT,3 25μg/kg) microinjected into hippocampal of mice impaired avoidance learning and memory abilities.On the 4th training day,the avoidance latency decreased by 58 3% and 16 7% respectively in the control group and K BGT group compared with those relevant parameters on the lst training day.On the last training day ,there were 80% mice in the control group found the platform underwater,while there were only 33 3% mice in K BGT group found the platform in 60 times tests within the fixed time.On the sixth day when the platform was removed,the mean numbers of mice swimming across the location areas where the platform was originally placed in the control group was 5 3±28, whereas the same parameter in K BGT was 1 9±1 2.In the step through test, the latency in K BGT group decreased by 38 3% and the rate of errors within 5 min increased 2 25 folds compared with the control group.At the dose of 40mg/kg,lecithin had no improving effects on the avoidance learning and spatial memory abilities in normal mice on 14 day oral administration,but improved the learning and memory abilities in mice impaired by K BGT.