Koda Tomoko, Kuroda Yoshiki, Ueno Yasuhiro, Kitadate Kentaro, Imai Hideki
Division of Environmental Health Sciences, Department of Social Medicine, Faculty of Medicine, University of Miyazaki, Miyazaki, Japan.
Nihon Eiseigaku Zasshi. 2008 Jul;63(4):711-6. doi: 10.1265/jjh.63.711.
The main objective of this study is to clarify the protective effects of buckwheat hull extract (BWHE) against toxicant-induced spatial memory impairment and hippocampal neuron injury in rats.
Male Sprague-Dawley (Jsl: SD) rats were fed chow containing 0.75% (w/w) BWHE during the experimental period. Two weeks after the start of the experiment, trimethyltin (TMT) (8 mg/kg bw) was administered orally to 6-week-old rats. After another two weeks, the rats were subjected to the Morris water maze task, which was used to determine spatial memory impairment. On the day after the Morris water maze task was performed, the right hemi-hippocampi were removed from the right half of the brain and weighed. Coronal sections of the left half of the brain were cut into 16-mum sections using a cryostat, and the number of neurons in each hippocampal region was evaluated by counting the surviving neurons using a light microscope.
The impairment of spatial memory and the decrease in the hippocampal weight were observed after the TMT administration. Prolonged supplementation of BWHE seemed to reverse these TMT-induced toxic effects, and also improved the spatial memory of rats.
The present results suggest that the BWHE supplementation of foods enhanced the spatial memory of rats and may have protective effects against hippocampal neurodegeneration accompanied by spatial memory impairment.
本研究的主要目的是阐明荞麦壳提取物（BWHE）对大鼠中毒性诱导的空间记忆损伤和海马神经元损伤的保护作用。
在实验期间，给雄性斯普拉格-道利（Jsl:SD）大鼠喂食含0.75%（w/w）BWHE的饲料。实验开始两周后，给6周龄大鼠口服三甲基锡（TMT）（8mg/kg体重）。再过两周后，对大鼠进行莫里斯水迷宫任务，以确定空间记忆损伤情况。在进行莫里斯水迷宫任务后的第二天，从大鼠右半脑取出右半侧海马称重。使用冷冻切片机将左半脑的冠状切片切成16μm厚的切片，通过光学显微镜计数存活神经元来评估每个海马区域的神经元数量。
给予TMT后观察到空间记忆损伤和海马重量减轻。长期补充BWHE似乎可以逆转这些TMT诱导的毒性作用，还能改善大鼠的空间记忆。
目前的结果表明，在食物中补充BWHE可增强大鼠的空间记忆，并且可能对伴有空间记忆损伤的海马神经退行性变具有保护作用。
