The Effect Of HiLO On Myocardial Morphology And Antioxidant Ability Of Male Rats

Objective:In order to provide scientific reference for hypoxic training. Through investigating the effect of Hilo on rats' myocardial morphology and it' s anti-injury adaptive change.Methods:140 male Sprague-Dawley rats were randomly divided into four groups:normoxia control group,intermittent hypoxic control group, normoxia training group,Hilo group.Each group was further subdivided into one day,seven days,28 days and/or seven days reoxygenation group. We employed the 13.6%concentrations of oxygen in the hypoxic tent.Results:1.Using transmission electron microscopy to observe the myocardial ultrastructure,the first day of Hilo group,myocardial ultrastructure of rats occurred injury,myofibrillar disarray evidently or dissolved,mitochondrial swelling,ridge dissolved unclear.In the first seven days,myocardial injury still exists,after 28 days of Hilo and reoxygenation seven-days,the damage of myocardial ultrastructure has been restored,and the number of mitochondria increased,the ridge dense,muscle fibers arranged in neat rows.All were clear.2.Free radical metabolism of myocardial and serum CK-MB.(1) Hilo group one day. myocardial MDA and serum CK-MB were the highest activity,compared with intermittent hypoxic control group and normoxia training group,had a very significant difference(p＜0.01);7 days,the MDA content and serum CK-MB activity,compared with the first day,had no significant difference.With the extension of the training cycle,there were downward trend of MDA and CK-MB in the experimental section.28 days,the MDA content and serum CK-MB activity,compared with the first day,had a significant decrease(p＜0.01).(2) Hilo group one day,myocardial SOD,T-AOC were the highest activity,compared with intermittent hypoxic control group and normoxia training group,had a significant difference (p＜0.05);7 days experimental,myocardial SOD,T-AOC activity,compared with the first day,had no significant difference.With the extension of the training cycle,improve antioxidant enzymes,28 days experimental, myocardial SOD.T-AOC activity,compared with the first day,had a significant increase(p＜0.01). Conclusion:(1) Hilo initial stage,the dual stimulation of hypoxia and exercise,free radicals increased;there were some injuries of myocardial ultrastructural,CK-MB activity increased.(2) After 28 days of Hilo and reoxygenation seven-day meet,myocardial activity of antioxidant increased,myocardial morphology were normal,and the number of mitochondria and crest increased.(3) Through studying myocardial morphology,free radical metabolism and serum CK-MB level,we observed that the myocardial injury induced by 3500m Hilo was irreversible,and with the adaptation of hypoxia,myocardial function enhanced and had good resistance against injury.