グルタミン酸脱水素酵素に関する研究

第1報その測定法, 体内分布, および血清内変動について

抄録

GLDH activity in rabbit liver was measured spectrophotometrically using reduced nicotineamide adenine dinucleotide (NADH) oxidation reaction. Optimum condition for mea-surement was obtained in a reaction mixture of 1/10 M of phosphate buffer (pH 8.6), 1/8 M of α-ketoglutarate and 2 M NH₄Cl.
Rabbit was used as a experimental animal thoughout. In liver the highest GLDH activity was obtained, while lower activities were found in kidney, lung, small intestine and skeletal muscle.
The GLDH was mainly located in mitocondrial fraction. A small amount of GLDH activity was found in nuclear fraction and almost no activity was found in supernatant fraction.
When it was kept in freezer (-20°C) for 24 hrs., 15% of GLDH activity was lost and then it was stable for a week.
In sera of normal 15 Japanese blood donors, mean of GLDH activity was 0.56 mU/ml (0-1.2 mU/ml) .
In cases of hepatitis, higher GLDH activity, while in cases of the other disease no change were observed. In rabbits with acute toxic hepatitis induced by carbon tetrahydro-chloride, higher activity was obtained in the early stages and the changes of value of GLDH were paralleled with that of GOT and not paralleled with that of LDH.