The Research On Hilo's Influnce On The Dynamic Change Of Male Rats' Synthase Activities Of Myocardial Energy Metabolism

Object:The hypoxic training methods are widely studied since 1968.But different training styles may cause different results.Heart is an important part of kinetic system.Hypoxia acclimatization,especially under the process of exercise could lead lots of physiological changes that propitious to aerobic capability.We studied the effect of hypoxic on the myocardial ultrastructure and aerobic oxidation function of rest and training rats in order to make full realize of the HiLo training on bodies.Materials and Methods:140 male Spargue-Dawley rats were randomly divided into 4 groups: normoxia control group(N),intermittent hypoxic group(H),normoxia training group(T) and HiLo group(HT).N and T are both divided into 3 sub-groups as the time that lday,7days and 28days;H and HT are both divided into 4 sub-groups as the time that lday,7day,8days and 7days after the intermittent hypoxic.Therefore there are totally 14 sub-groups, each one with 10 rats.After all the groups had been adapted for one week, the T and HT performed closely monitored training in treadmills(grade of 5,at the speed of 20m/min,duration of lh/day,6 days/week) for 4 weeks;the last HT group performed one more week after the hypoxia training.(All the trainings are out of the tent) During the 4 weeks experimental period,we employed the 13.6%concentration of oxygen(equal to altitude 3500m) in the hypoxic tent.H and HT groups were exposed to hypoxia for 12h every day.Sample collection and measurements were performed when the hypoxic groups just got out of the tent.The indexes we measured contains that the ATP synthase activity,the LDH synthase activity,the SDH synthase activity of myocardial.and the morphological observation. 1.In contrast to the N groups,the ATP synthase activity of myocardial increased significantly in the H groups;In the T groups,there was slightly decrease in the lday sub-group.And it respectively increased 7.9%and 32.2%in the 7days and 28days sub-groups;In the HT groups,it increased 40.7%,92.9%and 109.2%in the 7days,28days and 7days after the intermittent hypoxic sub-groups respectively.2.In contrast to the N groups,the LDH synthase activity of myocardial had just a slightly increased in all the intermittent hypoxic sub-groups; In the T groups,it increased 6.5%and 8.4%in the 7days and 28days sub-groups respectively;In the HT groups,it respectively increased 8.6%,13.8%,16.3%in the 7days,28days and 7days after the intermittent hypoxic sub-groups.In addition,the LDH synthase activity of myocardial slightly decreased in lday sub-groups of T and HT.3.In contrast to the N groups,the SDH synthase activity of myocardial respectively increased 31.4%,12.7%and 23.7;5.0%and 24.6%;34.5%, 61.8%and 75.9%in H,NT and HTs' 7days,28days and 7days after the intermittent hypoxic sub-groups.4.Myocardial ultrastructure of mitochondria,myofibrils and myofilament were observed by transmission electron microscope.The results show that HiLo training could improve ultrastructure of mitochondria,myofibrils and myofilament.Therefore the aerobic metabolism ability and energy utilization would be strengthened as a result.Conclusion:1.During the process of 4 weeks HiLo and 1 week training after HiLo, the SDH synthase,LDH synthase and ATP synthase activity of myocardial increased obviously as time passes by.The results show that HiLo training can improve the myocardial synthase ability,hence strengthen the myocardial aerobic oxidation effectively. 2.The hypoxia acclimatization and endurance training of 4 weeks can improve the myocardial ultrastructure,making the mitochondria get more and the density of mitochondrial crista get high.The aerobic metabolism ability got strongly impoved,especially during the days after the intermittent hypoxic.