偏二甲基肼中毒的病理学特点及近远期损伤效应研究

目的 探讨火箭推进剂偏二甲基肼(UDMH)中毒损伤的病理学特点及近期和远期损伤效应。方法 128只雄性Wistar大鼠随机分为UDMH近期和远期效应组及相应对照组,每组各8只动物。将动物置于120 L染毒柜内,注入推进剂级液态UDMH,保持染毒柜中UDMH质量浓度为8×10-4g／m3,染毒时间15 min。UDMH近期效应组于染毒后3、6、12、24、48和72 h活杀大鼠;远期效应组染毒后将动物做好标记,喂养1年。行主要器官病理形态学检查以观察UDMH染毒大鼠的近期和远期损伤效应。结果 UDMH近期效应组大鼠主要病理表现为神经系统损伤,以脑水肿为著,表现为神经细胞变性、坏死,神经轴突脱髓鞘、崩解,脑组织水肿,毛细血管扩张、充血;同时肝、肾、肺、心、脾、胃肠、胸腺、血液及骨髓等组织器官均有不同程度损伤。UDMH远期效应组大鼠1年后仍有大脑皮质神经元缺血性改变,丘脑及延髓传导束有出血及液化灶,传导纤维有解离、断裂、粗细不等、迂曲。结论UDMH中毒后2-6 h是伤情最严重的时期,中毒1年后远期损伤效应仍很明显;中枢神经系统是UDMH中毒致伤的最主要靶器官;对UDMH致伤后可能发生的远期损伤效应要进行兼顾和并治。

Intoxication induced by unsymmetrical dimethylhydrazine:characteristics and mechanism of its acute and chronic injuries

OBJECTIVE: To investigate the characteristics and mechanism of the acute and chronic injuries induced by unsymmetrical dimethylhydrazine (UDMH). METHODS: A total of 128 male rats were randomly divided into four groups: UDMH intoxication acute response group and chronic response group, and corresponding control groups. UDMH was administrated through inhalation at the concentration of 8x10(-4)g/m(3) for 15 minutes. Animals of each group were sacrificed at 3, 6, 12, 24, 48 and 72 hours respectively after the intoxication. Pathologic changes and blood gas were examined. Chronic injuries and pathologic changes were also observed 1 year after the intoxication. RESULTS: Major pathological changes in the intoxication group were cerebral edema, degeneration and necrosis of neuron, enlargement and hemorrhage of capillary. Damages of different degree were found in liver, kidney, lung, heart, spleen, stomach, intestine, thymus, blood, bone marrow. Pallium ischemia was also found in the intoxicated rats 1 year after the intoxication, including ischemia damage of neuron in cerebral cortex, hemorrhage and focal liquefaction of thalamencephalon and medulla conducting bind, dissociation, rupture, not uniform circuitry in conducting fibers. CONCLUSION: Our study reveals the basical pathological induced by intoxication of UDMH. The most severe stage of the injury appears 2-6 hours after intoxication. Long term investigation reveals pallium ischemia, thalamus hemorrhage and liquefaction in the medulla oblongata 1 year after the intoxication with UDMH. All the changes are significant.