The Elementary Study For Mechanism Of Aerobic Oxidation To Glycolysis In Rats Submitted To Swimming Exercise With Increasing Intensity

The reason of the aerobic oxidation to glycolysis is often taken as a sign of tissue hypoxia. When the exercise is reach some intensity, which inspired O2 is not need the metabolism in human body, which make the tissue hypoxia and accelerate the speed of glycolysis and accumulate the blood lactate. This thinking has led to the anaerobic threshold hypothesis, which links lactate generation in exercise muscle to an intracellular O2 limitation. It is well known that in human subjects lactate (LA)concentration in blood increase exponentially with exercise intensity, although anaerobiosis as a cause of the accelerated LA production has been questioned. There is recent controversy, however, on whether the lactate increasing during exercise relates at all to the adequacy of O2 availability for energy production in the exercising muscle.The objective of this study was to establish a model of swimming exercise with progressive intensities for rats, which in order to confirm the intensity of lactate threshold(LT); During graded incremental swimming exercise, blood was collected and investigate venous lactate concentration, venous pyruvate, venous PO2 at the intensity of LT, in order to discuss the reason of metabolism; The rats were submitted to an incremental swimming test in a relative pressurized cylinder tank, which full the 30% oxygen, which at the same intensity of LT, blood was collected and investigate venous lactate concentration, venous pyruvate, venous PO2, in order to discuss the relation between metabolism and oxygen of supply.Results show: (1) Our study clearly demonstrated that in rats, swimming with increasing intensity, changes in blood lactate show a pattern similar to that described in human subjects. So we can say the model is signification. (2) There is no significant difference lactate concentration and venous pyruvate and PO2, at break points and even given fraction of inspired O2 at break points. The lactate concentration is unrelated to PO2, and even given fraction of inspired O2 at break points, which explain there is no relation with oxygen when the aerobic oxidation to glycolysis. Even in full oxygen the aerobic oxidation also translate into glycolysis. (3) Aanalyse the venous pyruvate and lactate at rest and break point,which indirectly indicate the pyruvate can notpermeat the muscle membrance,but lactate can do, which also prove the hypothsis that pyruvate translate into lactate in order to prevent accumulate in the cytosol, which assure the pathway of glycolysis is smooth, which assure the necessity of energy.