Lung injury of rats induced by combined hypoxia and NaCN intoxication / 解放军医学杂志

ABSTRACT

Objective To explore the effects of oxidative stress and pulmonary vascular permeability on lung injury in rats treated with sodium cyanide(NaCN) and /or hypobaric hypoxia.Methods A total of 72 male SD rats were randomly divided into 2 groups the NaCN intoxicated group in 308m altitude and the hypobaric hypoxia combined NaCN intoxicated group in 4 000m high altitude.The animals for the experiment of hypoxia were processed in an artificial hypobaric chamber to simulate the designated high altitude hypoxia(4 000m,61kPa).NaCN was injected subcutaneously to the rats in the both groups at the dosage of 3.6mg/kg.Broncho-alveolar lavage fluid(BALF) and lung tissues were prepared at the time points of 0,0.5,1.0,2.0,4.0 and 6.0h.The activity of SOD,GSH-PX,ACE,LDH,AKP and the content of MDA,GSH,Evan's blue(EB) were detected by spectrophotometric method.Results Combined acute hypobaric hypoxia and NaCN intoxication produced a significant increasing effect on EB content in the rats.The activity of ACE,LDH and AKP in BALF,and the contents of MDA in BALF and lung tissue reached the highest value at 0.5h preparation at the combined hypobaric hypoxia and NaCN intoxicated group,but they were still higher than that of control group(NaCN intoxicated only);correspondingly the activity of SOD,GSH-PX,content of GSH in lung tissue and BALF reached the lowest value at 0.5h preparation at the combined hypobaric hypoxia and NaCN intoxicated group,but they were still lower than that of control NaCN intoxicated group.Conclusion The results suggest that under the condition of hypoxia,NaCN intoxication may produce severe harmful effects on the lungs,increase the pulmonary vascular permeability,and cause severe interference on to the oxidative stress level.