饮食中不同硒含量对大鼠行为及单胺类神经递质的影响

Effects of different concentrations of selenium in the diet on rats' behavior and monoamine neurotransmitters

目的研究微量元素硒对大鼠行为及神经递质的影响。方法将90只SD雄性幼鼠随机分为3组:低硒组(对照组)、富硒组、高硒组。分别喂饲低硒饲料及超纯水、低硒饲料及0.3 mg/L含硒超纯水、低硒饲料及0.6 mg/L含硒超纯水。观察大鼠行为,并分别于第4周、第8周、第12周各取10只大鼠行旷场试验,并检测血清5-羟色胺、多巴胺、去甲肾上腺素含量,于12周末处死余下所有大鼠后对大鼠心脏及肝组织进行病理学检查,了解不同含硒饮食对大鼠重要脏器的影响。结果试验初期各组大鼠行为相当,自第2周末低硒组大鼠较其余两组明显活跃,打架增多;第4周、第8周、第12周末各组大鼠旷场试验显示低硒组中央格停留时间明显短于富硒组及高硒组(P<0.05),穿格次数、站立次数及修饰时间明显高于其余两组(P<0.05),而富硒组、高硒组比较各项指标无显著性差异(P>0.05);相应的血清神经递质含量显示各时段末低硒组5-羟色胺、去甲肾上腺素含量均低于富硒组及高硒组(P<0.05),多巴胺含量显著高于其余两组(P<0.05),富硒高硒组比较无显著差异(P>0.05)。12周末各组大鼠肝脏、心脏外观无异常,低硒组、富硒组肝脏均有少许点状坏死及较多核分裂,心肌组织可见细胞核深染增大,高硒组上述病理改变相对较少。结论饮食中的硒含量高低可影响大鼠行为及血清单胺类神经递质含量。低硒饮食可导致大鼠多动、增加恐惧情绪,富硒及高硒饮食可维持大鼠情绪,减少多动行为。神经递质含量并不与饮食硒含量呈线性关系。

Objective To study the effect of selenium on rats behavior and neurotransmitter. Methods 90 male SD rats were randomly divided into 3 groups： Se-poor group （control group）, Se-rich group and Se-high group. All groups were fed with poor selenium diet and Se-poor group were given ultra pure water by gavage, Se-rich group were given ultra pure water with selenium containing 0.3 mg/L, Se-high group were given ultra pure water with selenium containing 0.6 mg/L. To observe the behavior of rats, and in fourth weeks, eighth weeks, twelfth weeks, 10 rats from each row were selected to perform the open field test, serum 5- serotonin, dopamine, norepinephrine were detected. The rates were sacrificed at 12 weeks to detect the heart and liver pathological tissue. The effects of different selenium containing diet on vital organs in rats were analyzed. Results The rats behavior was not significant difference at the beginning of the experiment, from the second weekend the Se-poor group were active and pugnacity compared with the other two groups. In the open field at the fourth weekend, eighth weekend and the twelfth weekend, the central grille time of the Se-poor group was shorter than the Se-rich group and Se-high group （ P 〈0.05）. The number of crossing line, stand number and modification time were significantly higher than the other two groups （ P 〈0.05）, and the Se-rich group, compared with the index of the se-high group had no significant difference （ P 〉0.05）. At the end of the period, the levels of 5-Serotonin and norepinephrine levels of Se-poor group were lower than the other two group＇s （ P 〈0.05）, however the level of dopamine was significantly higher than the other two groups＇ （ P 〈0.05）, there was no significant difference between the Se-rich group and the Se-high group （ P 〉0.05）. At the 12th weekend, the rats＇ livers and hearts had no abnormal appearance;under the microscope the liver had a little spotty necrosis and more nuclear fission in Se-poor group and Se-rich group, myocardial tissue visible with hyperchromatic nuclei increases, but the pathological change was relatively small in the Se-high group. Conclusion The level of selenium in the diet can affect the behavior of rats and the levels of monoamine neurotransmitters. Poor selenium diet can lead to hyperactivity and fear in rats, rich selenium and high selenium diet can calm tension and reduce hyperactivity. Neurotransmitters and the level of dietary selenium is not a linear relationship.