缺氧复合氰化钠中毒对大鼠脑组织单胺类神经递质含量的影响

目的观察缺氧复合氰化钠(NaCN)中毒对大鼠脑组织单胺类神经递质含量的影响。方法128只雄性SD大鼠随机分为平原组和高原组,每组64只。平原组大鼠在常规实验室内处理,高原组于模拟海拔4 000m的高原低压舱内连续缺氧暴露3d,每天23.5h。高原组和平原组大鼠分别在模拟高原条件和平原条件下经腹腔注射NaCN 3.6mg/kg,于中毒0、0.5、2、6h麻醉取脑,冰上分离海马和纹状体组织,离心提取组织内蛋白质。HPLC法测定大鼠脑纹状体和海马组织多巴胺(DA)、去甲肾上腺素(NE)和5-羟色胺(5-HT)含量。结果平原组大鼠NaCN中毒0.5、2、6h脑纹状体和海马组织的DA、NE和5-HT含量与中毒0h比较变化不明显。高原组大鼠脑纹状体DA、NE、5-HT含量和海马组织NE、5-HT含量在NaCN中毒2h或6h与0h比较均显著下降。与平原组比较,高原组纹状体DA、NE、5-HT和海马组织NE、5-HT含量均明显降低(P<0.05或0.01)。结论高原缺氧后脑组织单胺类神经递质含量明显降低,而氰化物中毒可进一步加剧这一改变。

Effects of combined hypoxia and NaCN intoxication on the contents of monoamine neurotransmitters in rat brain

Objective To investigate the effects of sodium cyanide(NaCN) and /or acute hypobaric hypoxia on the contents of monoamine neurotransmitters in rats' brain.Methods 128 adult male SD rats were divided into normoxic group and acute hypoxia group with 64 animals for each group.An artificial hypobaric hypoxia chamber was used to simulate a 4 000m altitude situation.The acute hypoxic exposure models were established by exposing rats to the hypobaric chamber for 3 days.All the rats were then injected intra-peritoneally with NaCN in a dosage of 3.6mg/kg at sea level and at simulated high altitude at 0,0.5,2 and 6h time points.The rats were sacrificed and the brains were isolated.The brain tissues of hippocampus and striatum corpora were then dissected on ice.Proteins of the brain tissue were extracted by centrifugation.Contents of dopamine(DA),epinephrine(NE) and 5-hydroxytryptamine(5-HT) in the brain tissues were analyzed by HPLC.Results NaCN intoxication did not affect the contents of DA,NE and 5-HT at 0.5h,2h and 6h in the selected brain tissues of the normoxic group.Compared with non-intoxication group,however,NaCN intoxication for 2h or 6h significantly decreased the levels of NE and 5-HT in the hippocampus tissues and the contents of DA,NE and 5-HT in striatum corpora in acute hypobaric hypoxia group.The contents of DA,NE and 5-HT in striatum corpora and the contents of NE and 5-HT in acute hypoxia group were significantly decreased compared with that in normoxic group(P<0.05,P<0.01).Conclusion Acute hypobaric hypoxia may significant affect the contents of monoamine neurotransmitters in brain tissues.This effect could be promoted by NaCN intoxication.