| Lactate is an important intermediary metabolism substance of organisms. This thesis takes toads raised at different temperatures as its objects of study, analyzes the relations between the lactate produced in different tissues (serum, heart, liver and skeletal muscles) and NADH. As results shows, there is an obvious anti-correlation between lactate and NADH/NAD+ rate (serum k=-8.0129, R2=0.8975; heart k= -0.9965, R2=0.8824; liver k=-0.3304, R2=0.7565; skeletal muscles k=-2.6470, R2=0.8466), meaning when the content of lactate is high, the NADH/NAD+ rate is comparatively small. In this case, lactate is turned into pyruvate and NADH by lactate dehydrogenase. NADH is produced to secure the minimum storage of energy, which should be used to refresh the organisms and to keep the balance of oxidation reduction.Researches on the energy metabolism processes of organisms are of considerable importance. This thesis mainly focuses on the turbulence of energy charge in different toads tissues. The research discovered that at the temperatures of 5, 10 and 20℃, the energy charge of liver reaches the highest level. Therefore, energy supply to liver during hibernation is necessary. At the temperature of 25℃, the energy charge level of heart reaches the highest level, meaning, in normal conditions when toads move constantly, the body provides the heart with large quantity of energy in a continuous manner, for the sake of normally-run physical activities. At the temperatures of 15 and 30℃, toads are quite energetic and active. Therefore, the requirement of energy on the part of skeletal muscles hits the peak, i.e. their energy charge is at the highest level. Based on these researches, a conclusion is reached that the energy charges of various toad tissues will change as temperature changes, which may serve as the basis of other researches on the energy metabolism process of toads.In this thesis, the network of lactate metabolism process is constructed, as far as toads are concerned. The flux distribution model generated in this case shows that the turbulence pattern of lactate in heart is similar to that in liver– both reaches the highest point at the temperatures of 5 and 30℃. On the other hand, the turbulence pattern of lactate in serum is also similar to that in skeletal muscles– the highest point is at 25℃. A control coefficient Cpi is calculated out, based on the analysis of all main components with temperature as the perturbation factor. It shows that MDH has served the function of negative accommodation in all four samples, but the maximum controlling coefficients differ from each other– PGK in serum (Cp PGK= 0.1186), LDH in heart (CpLDH= 0.1160), LDH in liver (CpLDH= 0.1296), and HK in skeletal muscles (CpHK= 0.1883). Moreover, another flux control coefficient CJi is calculated out with a lin-log method. It shows that, in various tissues, the following substances have the highest controlling impact: HK in serum (CpHK= 0.1532), ALD in heart (CpALD= 0.1732), PK in liver (CpPK= 0.1439), and HK in skeletal muscles (CpHK= 0.2641). The values of all MDH are unexceptionally negative, and the G6PDH in heart also serves the function of negative accommodation. At last, the author compared the control coefficients of both parts, discovering that there is an obvious uniformity among serum, heart and liver, while the changing patterns of the control coefficients in both samples of skeletal muscles are basically identical, which means that the control coefficients generated by analyzing the main components have reflected the metabolism control mechanism of 12 kinds of lactate existing in toads in a fairly satisfying manner. What's more, using this new method can avoid those problems encountered in traditional analyzing methods, and therefore providing a more convenient method for the analysis of network controlling in terms of metabolism researches.
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