Kimani Samuel Thuu, Nyongesa Albert Wafula
Department of Medical Physiology, University of Nairobi, P.O. Box 30197, Nairobi, Kenya.
Behav Brain Res. 2008 Dec 16;195(1):192-7. doi: 10.1016/j.bbr.2008.05.022. Epub 2008 Jun 6.
This study investigated the effects of fresh khat extract on learning and memory in CBA mice. A total of 20 male CBA mice, weighing 20-30 g, 5-6 weeks old were administered intraperitoneally with a single daily dose of khat extract for 5 days. The animals were divided into four groups, each comprising five animals. The first three groups were administered three doses (40, 120 and 360 mg/kg body weight) of khat extract, respectively. The last group served as controls and was administered with 0.5 ml normal saline intraperitoneally. The animals were then subjected to Morris water maze (MWM) task performance. Moderate and high doses (120 and 360 mg/kg body weight) of khat extract significantly impaired (P<0.05) while low dose (40 mg/kg body weight) of khat extract did not have a significant effect on CBA mice acquisition learning. The high dose of khat extract significantly (P<0.05) improved while moderate and low doses impaired accuracy for spatial memory of the platform location. This study has shown that khat extract has selective effect on spatial learning and memory, with low dose having no effect on learning but impairing memory, whereas high dose impairs learning but improves memory.
本研究调查了新鲜巧茶提取物对CBA小鼠学习和记忆的影响。选取20只体重20 - 30克、5 - 6周龄的雄性CBA小鼠，每天腹腔注射一次巧茶提取物，连续注射5天。将动物分为四组，每组五只。前三组分别给予三种剂量（40、120和360毫克/千克体重）的巧茶提取物。最后一组作为对照组，腹腔注射0.5毫升生理盐水。然后让动物进行莫里斯水迷宫（MWM）任务表现测试。中等剂量和高剂量（120和360毫克/千克体重）的巧茶提取物显著损害（P<0.05）CBA小鼠的习得性学习，而低剂量（40毫克/千克体重）的巧茶提取物对其没有显著影响。高剂量的巧茶提取物显著（P<0.05）提高了平台位置空间记忆的准确性，而中等剂量和低剂量则损害了该准确性。本研究表明，巧茶提取物对空间学习和记忆有选择性作用，低剂量对学习无影响但损害记忆，而高剂量损害学习但改善记忆。
