The preventing effect of oxygen enriched environment at physiological equivalent altitudes on the high altitude pulmonary edema of rat
10.3760/cma.j.issn.1007-6239.2011.04.004
- VernacularTitle:不同生理等效高度的富氧环境对大鼠急进高原肺水肿的防护作用
- Author:
Hua-jun XIAO
1
;
Chang-lei DENG
;
Dong-qing WEN
;
Gui-you WANG
;
Zhao GU
;
Xiao-peng LIU
;
Li-shan FU
;
Juan CHEN
;
Wei-ru SHI
;
Bo ZHANG
Author Information
1. 空军航空医学研究所, 北京,100142
- Publication Type:Journal Article
- Keywords:
Altitude;
Anoxia;
Pulmonary edema;
Rats;
Atmosphere exposure chamber;
Oxygen enriched environment
- From:
Chinese Journal of Aerospace Medicine
2011;22(4):259-264
- CountryChina
- Language:Chinese
-
Abstract:
Objective To study the preventing effect of oxygen enriched environment at physiological equivalent altitudes on high altitude pulmonary edema (HAPE) by HAPE animal model Methods Fifty male Wistar rats were randomly and averagely divided into ground control group,hypoxia group,oxygen enrichment group 1,oxygen enrichment group 2 and oxygen enrichment group 3.Groups were exposed to 6000 m with the climbing rate of 10 m/s in altitude chamber,except ground control group.Meanwhile,hypoxia group was supplied with air and oxygen enrichment group 1 and 2 were supplied with gas that contained 35％ and 30％ oxygen respectively.Oxygen enrichment group 3 was alternatively supplied with air or gas that contain 35 ％ oxygen every 4 h with the flow rate of 7 L/min.The chamber was descended to ground level after 24 h experiment.The water ratio of the left lung of rat was examined,the prefrontal lobe of right lung was taken for pathological observing,the middle and posterior lobe of the right lung were taken to detect the concentration of endothelin-1 (ET-1) and nitricoxide synthase (NOS) activity respectively. Results The water ratio of lung among every group presented significant difference.Ground control group showed the lowest water ratio (0.80％± 0.01％) and significantly different with that of other groups (P＜0.01).The water ratio of hypoxia group was 0.83％ + 0.01％,which was significantly higher than that of ground control group and oxygen enrichment group 3 (P＜0.01).The water ratio of rich oxygen group 2 was 0.81％ + 0.01％,which was obviously lower than that of oxygen enrichment group 1 and oxygen enrichment group 3 (P＜0.05).The pathology result showed that the rat lung of all the experiment groups presented severe to mild changes of interstitium pulmonary edema with the sequence of hypoxia group,oxygen enrichment group 2,oxygen enrichment group 1 and oxygen enrichment group 3.And there were no significant ET-1 concentration difference among every group. The NOS activity of ground control group was (1.49±0.24) U/mg,which was the highest in groups (P＜0.01),and the NOS activity of hypoxia group was (0.78 + 0.28) U/mg,which was the lowest among all groups (P＜0.01).Compared with the hypoxia group,the NOS activity of oxygen enrichment group 1 and oxygen enrichment group 3 was more energetic [(1.06 + 0.17) U/mg,(1.09 + 0.20) U/mg,P＜0.01]. Conclusions Serious HAPE happens on the rats that stayed at 6000 m for 24 h.By making 35％ oxygen enriched environment (physiological equivalent altitude of 2500 m) or supplying with 70 mm Hg oxygen partial pressure of inspired air would effectively prevent rat from HAPE.But there is no significant protection effect by supplying with 30％ oxygen concentration (physiological equivalent altitude is 3500 m) or setting up 56 mm Hg oxygen partial pressure of inspired air.Intermittent supplement of 35％ oxygen every 4 h would also effectively prevent rat from HAPE at 6000 m.
