Study on myocardium and brain damage in rats by simulating high altitude / 药学实践杂志

ABSTRACT

Objective To investigate the effect of hypoxia with cold on the heart and brain damage in rats by simulating 6 000 m high altitude at different exposure time,established a rat model of acute mountain sickness for the related mechanism studies.Methods 32 healthy male Wistar rats were randomly divided into normal control group,hypoxia with cold 1 d,3 d and 5 d group,8 rats in each group.The normal control group was kept in the plain environment(1 500 m)without any treat-ment.The other three groups were placed in large hypobaric hypoxia chamber to simulate 6 000 m altitude with different ex-posed times.HE staining was used to observe the pathological changes of heart and brain tissue.The changes of biochemical indexes were measured to evaluate the damage of heart and brain tissue at different hypoxia times.Results HE staining showed that hypoxia with cold induced rat heart and brain damage with different degrees.The myocardial tissue damage was in-creased with exposure time.The most serious brain damage happened in day 3.Compared with the normal control group,the content of MDA and LD in the myocardial tissue of hypoxia rats were significantly increased(P<0.05 or P<0.01)with pro-longed time,while the contents of GSH,T-SOD and the activity of Na+K+-ATPase were reduced(P<0.05 or P<0.01). The content of MDA in brain tissue was significantly increased at day 1 and day 3(P<0.05 or P<0.01).LD content was sig-nificantly increased(P<0.05)with time.The content of GSH,the activity of T-SOD and Na+K+-ATPase were significantly reduced in day 3(P<0.05).Conclusion Simulating an altitude of 6 000 m caused obvious damage on the heart and brain tis-sues of rats.The degree of damage was related to the exposure time to hypoxia with cold.The decrease of body′s antioxidant capacity,the increase of free radicals and energy metabolism disorders are important factors leading to heart and brain injury.