不同剂量维生素E对慢性间断性缺氧大鼠记忆能力及脑内单胺类神经递质的影响

目的探讨不同剂量维生素E(VitaminE,VitE)对慢性间断性缺氧(chronicepisodichypoxia,EHYP)大鼠记忆能力和脑内单胺类神经递质水平的影响。方法建立EHYP大鼠模型,并给予大(每天50IU/250g体重)、小(每天5IU/250g体重)剂量VitE干预。通过被动避暗回避反应试验评价大鼠学习记忆能力,潜伏期(stepthroughlatency,STL)越长,记忆能力越强;用高效液相色谱电化学检测器(highperformanceliquidchromatographyandelectrochemicaldetection,HPLC-ECD)测定大鼠皮层、海马和纹状体内单胺类神经递质的含量。结果EHYP处理后,与对照组相比,EHYP组大鼠STL明显缩短(P<0.01),各脑区单胺类神经递质水平均显著降低(P<0.05)。药物干预后,与EHYP组相比,VitE大、小剂量组大鼠STL均显著延长(VitE大剂量组:P<0.05,VitE小剂量组:P<0.01),但大剂量组大鼠STL明显短于小剂量组(P<0.05);就单胺类神经递质水平而言,小剂量组大鼠皮层去甲肾上腺素(norepinephrine,NE)、多巴胺(dopamine,DA)含量,海马NE、DA、5-羟色胺(5-hydroxytryptamine,5-HT)含量和纹状体NE、DA、5-HT含量均显著升高(P<0.05),而大剂量组大鼠仅纹状体NE、DA、5-HT和海马5-HT水平显著升高(P<0.05)。结论VitE可改善EHYP大鼠记忆能力,并提高脑内单胺类神经递质水平,且小剂量疗

Effect of vitamin E on memory and brain monoaminergic neurotransmitter in chronic episodic hypoxia rat

OBJECTIVE: To investigate the effect of Vitamin E (VitE) on memory and brain monoaminergic neurotransmitter level in chronic episodic hypoxia (EHYP) rat. METHODS: VitE 50 IU/ (250 g.d) or 5 IU/ (250 g.d)] was given to the EHYP rat model. The memory was evaluated by the passive avoidance test and the levels of monoaminergic neurotransmitter, including norepinephrine (NE), dopamine (DA) and 5-hydroxytryptamine (5-HT), were determined in three different brain regions (including cerebral cortex, hippocampus and striatum) using high performance liquid chromatography and electrochemical detection (HPLC-ECD). RESULTS: The performance on passive avoidance test of EHYP rats was worse than that of controlled rats (P < 0.01). The performance of rats in two different treatment groups was better than that of EHYP rats (P < 0.05), the performance of rats in high-dose group was worse than that of rats in low-dose group (P < 0.05). Compared with controlled rats, levels of monoaminergic neurotransmitters in different brain regions of EHYP rats decreased significantly (P < 0.05). Compared with EHYP rats, level of NE and DA in cerebral cortex and level of monoamine (NE, DA, and 5-HT) in hippocampus and striatum of low-dose treated rats were increased significantly (P < 0.05). Different with low-dose treated rats, only level of monoamine (NE, DA, and 5-HT) in striatum and level of 5-HT in hippocampus in high-dose treated rats were increased significantly (P < 0.05), as compared with the EHYP rats. CONCLUSIONS: vitE can improve memory and increase brain monoaminergic neurotransmitter of EHYP rats. Moreover, the effect of low-dose vitE is better than that of high-dose VitE.