兴奋性氨基酸与1,2-二氯乙烷急性中毒性脑病关系的探讨

目的　探讨兴奋性氨基酸 (EAAs)与 1 ,2 二氯乙烷 (1 ,2 DCE)急性中毒性脑病的关系。方法　将SD大鼠随机分为 7组 :对照组、3个染毒组 (5 .0、1 0 .0、2 0 .0g/m31 ,2 DCE)和 3个时间组(1 0 .0g/m31 ,2 DCE染毒后 2、4、6h) ;连续静式吸入染毒 1 2h ;干湿重法测定大鼠脑皮质和髓质含水量 ;高效液相色谱法 (HPLC)检测脑组织中谷氨酸 (Glu)、天冬氨酸 (Asp)、甘氨酸 (Gly)及γ 氨基丁酸(GABA)含量的变化。结果　 (1 )大鼠脑皮质和髓质含水量 :不同剂量染毒组大鼠脑皮质含水量分别为 76 .1 0 %± 1 .41 %、76 .45 %± 0 .75 %、79.95 %± 1 .45 % ,均高于对照组 (74.2 2 %± 1 .77% ) ,差异有显著性 (P <0 .0 5 ,P <0 .0 1 ) ;髓质含水量仅 2 0 .0g/m3组 (71 .77%± 3 .0 7% )有明显升高 ,差异有显著性(P <0 .0 5)。染毒后 2、4、6h脑皮质含水量分别为 79.36 %± 2 .1 0 %、79.48%± 1 .2 1 %、80 .64 %±1 .93 % ,均高于 1 0 .0g/m3即刻组 ,差异有显著性 (P <0 .0 5)。 (2 ) 4种氨基酸递质含量 :不同剂量染毒组Asp含量分别为 (4.83± 0 .35)、(7.1 7± 0 .40 )、(1 0 .52± 0 .39) μmol/g ;Glu含量分别为 (2 3 .86± 0 .62 )、(31 .2 1± 2 .50 )、(2 8.2 3± 1 .58) μmol/g;Gly含量分别为 (5 .59±

The relationship between excitatory amino acids and acute intoxicated encephalopathy induced by 1,2-dichloroethane

OBJECTIVE: To explore the relationship between excitatory amino acids (EAAs) and acute in toxicated encephalopathy induced by 1,2-dichloroethane (1,2-DCE). METHODS: SD rats were randomly divided into 7 groups: 1 control group, 3 exposure (5.0, 10.0, 20.0 g/m(3)) groups and 3 duration (2, 4, 6 h after 10.0 g/m(3) exposure) groups. Rats were exposed to 1,2-DCE for 12 h by continual static inhalation. Water content of cerebral cortex and medulla was measured by wet-dry method; 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). RESULTS: Water content of cerebral cortex in 3 exposure groups (76.10% +/- 1.41%, 76.45% +/- 0.75%, 79.95% +/- 1.45% respectively) were higher than that of control group (74.22% +/- 1.77%, P < 0.05, P < 0.01). That of medulla was increased significantly merely at 20.0 g/m(3) (71.77% +/- 3.07%, P < 0.05). Water content of cortex in 3 duration groups (79.36% +/- 2.10%, 79.48% +/- 1.21%, 80.64% +/- 1.93% respectively) were higher than that of 10.0 g/m(3) instant exposure group (P < 0.05). The content of Asp (4.83 +/- 0.35) micro mol/g, (7.17 +/- 0.40) micro mol/g, (10.52 +/- 0.39) micro mol/g], Glu (23.86 +/- 0.62) micro mol/g, (31.21 +/- 2.50) micro mol/g, (28.23 +/- 1.58) micro mol/g] and Gly (5.59 +/- 1.01) micro mol/g, (6.06 +/- 0.83) micro mol/g, (7.26 +/- 1.34) micro mol/g] in exposure groups were higher than those of corresponding control groups (3.72 +/- 0.48) micro mol/g, (21.09 +/- 1.20) micro mol/g, (3.83 +/- 0.44) micro mol/g, P < 0.05, P < 0.01]. Compared to 10.0 g/m(3) instant group, Asp content was increased at 2, 4, 6 h (P < 0.01), Glu content at 2, 4 h (P < 0.05), and peak value of Glu appeared at 4 h (35.40 +/- 2.40) micro mol/g] while Gly content was significantly decreased (P < 0.01). GABA did not show evident changes in both exposure or duration groups (P > 0.05). CONCLUSION: EAAs appears to be related with the development of acute intoxicated encephalopathy induced by 1,2-DCE, and its damage to neuron might be one of the mechanisms of brain edema.