에르릿히 복수종양의 C14-1-포도당 및 C14-6-포도당 대사에 관한 연구

• 영문명: Metabolism of C¹⁴-1-glucose and C¹⁴-1-glucose by the Ehrlich Ascites Turner Tissue
• 발행기관: 대한생리학회
• 저자명: 권창락(Kwon, Chang-Rak)
• 간행물 정보: 『대한생리학회지』제1권 제1호, 33~42쪽, 전체 10쪽
• 주제분류: 의약학 > 의학일반
• 파일형태: PDF
• 발행일자: 1967.06.30

영문 초록

The metabolic patterns of C-1 and C-6-carbon atoms of glucose were observed in the tissue homogenates of the Ehrlich ascites tumor tissue which was incubated for 3 hours in the Dubnuff metabolic shaking incubator. C¹⁴-1-and C¹⁴-6-glucose were used as tracers. The glucose media in which tissue homogenate was incubated was kept at a concentration of 200mg% glucose of carrier and appropriate amount of C¹⁴-1-and C¹⁴-6-tracer. At the end of 3 hour incubation, respiratory CO₂ samples trapped by alkaline which is placed in the tenter well of incubation flask were analyzed for the total CO₂ production rates and their radioactivities. The tissue homogenate samples after incubation were analyzed for their concentrations of glucose, lactate, pyruvate and glycogen and calculations were made on the glucose consumption rate, pyruvate and lactate accumulation rates. The following results were obtained. Data obtained in each group are as follows: 1. In the tissue homogenate, which was incubated with C¹⁴-1-glucose as a substrate, total CO₂ production rate averaged 19.0±5.0 μm/hr/gm and the mean specific activity of respiratory CO₂ was 840±296 cpm/mgC. Relative specific activity (RSA) which means the fraction of CO₂ derived from medium C¹⁴-6-glucose to total CO₂ production rate was calculated by ratio of SA of respiratory CO₂ and medium C¹⁴-1-glucose. RSA was 14.3±5.0% Accordingly actual CO₂ production rate from medium C¹⁴-6-glucose showed a mean value of 2.79±1.35 μM/hr/gm, of which amount was equivalent to the mean value of total glucose consumption rate (RGDco₂), namely, 5.1±1.3%. Lactate and pyruvate appearance rates averaged 7.13±1.26 and 0.21±0.02 μM/hr/gm, respectively. Assuming that these 3 carbon compounds appeared in the medium were derived from glucose, calculations were made that relative glucose disappearance rate into lactate (RGD_L) was 38.0±5.4% and RGD_P was 1.23±0.03%. Therefore, about 43.3% of the total glucose consumed were accounted for by conversion into the respiratory CO₂, lactate and pyruvate. 2. In the second group, which was incubated with C¹⁴-6-glucose as a substrate, glucose consumption rate, lactate and pyruvate appearance rates showed almost the same order as the values of the C¹⁴-6-glucose substrate group. However, RSA was remarkably decreased showing a mean value of 1.02±0.13%. This fact means that the C-6 carbon of glucose take the minor part in the oxidative metabolism of glucose. The glycogen level in both substrate tissue homogenate showed less than 0.3% of tissue weight. These low value suggested that there was an inhibition of carbohydrate synthesis in the Ehrlich ascites tumor tissue. 3. The catabolic pathway of glucose in the tumor tissue were analyzed on the basis of Bloom s principle from the values of RSA. It was found that in the tumor tissue more than 90% of CO₂ derived from glucose were oxidized via the alternate pathway other than principal EMP-TCA cycle such as hexose monophosphate pathway (HMP). From the data described above, it was assumed that in the Ehrlich tumor tissue anaerobic glycolysis proceeds normally although, the oxidation of products of anaerobic glycolysis via the TCA cycle is inhibited resulting in the accumulation of lactate and almost all of oxidative energy from glucose is released by oxidative pathway such as HMP.