叶酸缺乏的离乳大鼠空间学习记忆能力的检测及意义

探讨叶酸缺乏时离乳大鼠学习记忆能力的改变 ,应用 54只刚离乳的健康雄性SD大鼠 ,随机分成实验组、对饲组和对照组三组。实验组饲以去叶酸的RHAA配方饲料 ,另二组饲以添加了 8mg叶酸 /kg膳食的RHAA饲料 ,对饲组按实验组的进食量加以控制 ,但对照组不控制进食。每周记录体重和摄食量两次。分别于饲养第 2和第 6周末测定血清叶酸浓度和进行Morris水迷宫测试大鼠的学习记忆能力 ,记录平均逃避潜伏期和分析原平台象限游泳距离占游泳总距离的百分比 ;对血清叶酸浓度、逃避潜伏期及原平台象限游泳距离百分比做相关性分析。结果显示实验第 2周除实验组血清叶酸浓度降低外 ( p <0 0 1 ) ,其余各指标在三组间无明显差异 ( p >0 0 5)。实验组从第 3周、对饲组从第 4周开始摄食量减少 ,生长速度减慢 ( p <0 0 5) ;第 6周实验组的平均体重、血清叶酸浓度明显低于对照组和对饲组 ( p <0 0 1 ) ,平均逃避潜伏期明显延长 ,原平台象限游泳距离百分比明显下降。与对照组比较 ,对饲组上述指标的改变不明显 ( p >0 0 5)。相关分析结果表明 ,血清叶酸浓度与逃避潜伏期及原平台象限游泳距离百分比非常显著相关 (r =- 0 0 546 ,p <0 0 1 ;r =0 86 ,p <0 0 1 )。因此 ,可以结论 :叶酸缺乏可损害离乳大鼠的空间学习记忆

Quantitative analysis of folate deficiency on weanling kat's Leaming & memory

To verify the effect of folate deficiency on weanling rats' learning and memory, Using 54 male weanling Sprague Dawley rats were divided into three groups. The folate deficient group received an amino acid defined diet(RHAA), the ad libitum control group had the same diet supplemented with folate of 8mg per kg diet, and the pair fed control group received the folate supplemented diet, but was individually pair fed to the mean daily food consumption of the folate deficient group. Body weight and food intake were measured twice weekly. At the end of the second and sixth week of the experiment, Results showed growth retardation and impaired food intake associated with FD could not be demonstrated in the FD group rats until the end of the 3 rd week (p<0.05), while the pair fed group gradually showed this retardation at the end of the 4 th week. At the end of the experiment the FD rats had weight loss, leaving the pair fed group slightly affected (compared with ad libitum control group, p<0.05). Decreased serum folate occurred at the end of the 2 nd week of the experiment, without alteration of the other parameters. At the end of the 6 th week, FD group rats had very low body weight and serum folate concertration (p<0.01), with the mean escape latency lengthened and the percentage of swimming distance in the platform quadrant decreased. The fluorescence intensity of the hippocampal synaptosomal membrane increased, which implied reduced membrane fluidity (p<0.01). Correlation analysis results showed that the serum folate concentration, mean escape latency and the percentage of swimming distance in the platform quadrant were highly correlated (r= 0.527, p<0.01, r=0.86, p<0.01). Therefore folate deficiency could impair the learning and memory of weanling rats & the impairment was rather obvious at the 6th week.