全氟辛烷磺酸对大鼠脑组织氨基酸类神经递质和谷氨酰胺合成酶的影响

目的探讨全氟辛烷磺酸(PFOS)与大鼠中枢神经系统兴奋性氨基酸和谷氨酰胺合成酶(GS酶)的剂量反应关系。方法将20只成年雄性Wister大鼠随机分为4组(对照组、4个染毒组)每组5只。大鼠染毒PFOS(12.5、25、50mg/kg)5天后,对照组给予等体积的2%吐温-80溶液,应用高效液相色谱法测定脑组织氨基酸类神经递质及谷氨酰胺合成酶的改变。结果与对照组比较,大鼠自发活动能力下降;50mg/kg体重组海马谷氨酸含量显著降低,25和50mg/kg体重组皮质谷氨酸含量显著降低;随着染毒剂量的增加海马GS酶活性增加,其中12.5mg/kg剂量组和25mg/kg剂量组明显高于对照组(P<0.05)。结论氨基酸类神经递质含量的改变是PFOS神经毒性的机制之一。

Effects of perfluorooctane sulfonate on amino acid neurotransmitters and glutamine synthetase in rats

Objective To discuss the dose-effect of perfluorooctane sulfonate(PFOS) on excitatory amino acids (EAAs) and glutamine synthetase (GS) in rat central nerves system. Methods 20 mature male Wister rats were categorized into 4 groups randomly,5 rats every group.Wister rats were treated once by gastric perfusion method with12.5,25,50mg/kg PFOS and controls received same valume vehicle(2% tween-80)once orally. 5 days after treated,the rats in all groups were sacrificed. The contents of glutamate (Glu),aspartate (Asp),glycine(Gly) and gamma-aminobutyric acid(GABA) in brain tissues were determined by high performance liquid chromatography (HPLC). Changes in GS in brain tissue were observed GS kit. Results The spontaneous motor ability was decreased as compared with the controls. In hippocampus,the content of glutamate (Glu) was significantly decreased at the dose of 50mg/kg bw(P<0.05). In cortex,the content of glutamate (Glu) was significantly decreased at the dose of 25 and 50mg/kg bw(P<0.05).In hippocampus,increase with the dose of PFOSthere was significant difference of GS at 12.5 and 50mg/kg group compared with corresponding control group(P<0.05) Conclusion The altered content of amino acid neurotransmitters might be one of the important mechanisms of PFOS neurotoxicity.