Patent ID: 7192727

Claim:
In a method for measuring an alanine aminotransferase activity in a sample, said method comprising the steps of: bringing the sample into contact with L-alanine, 2-oxoglutaric acid, lactate dehydrogenase, and reduced nicotinamide adenine dinucleotide, generating pyruvic acid and L-glutamic acid from L-alanine and 2-oxoglutaric acid as substrates by alanine aminotransferase, converting pyruvic acid and reduced nicotinamide adenine dinucleotide to lactic acid and oxidized nicotinamide adenine dinucleotide by lactate dehydrogenase, and measuring a decreased amount of reduced nicotinamide adenine dinucleotide or an increased amount of oxidized nicotinamide adenine dinucleotide, the improvement comprising bringing the sample into contact with L-alanine, 2-oxoglutaric acid, lactate dehydrogenase, and reduced nicotinamide adenine dinucleotide in the presence of a substance having an activity of inhibiting a lactate dehydrogenase activity, said substance being selected from the group consisting of oxamic acid, oxalic acid, oxalacetic acid, pyruvic acid, phosphoenolpyruvic acid, sodium dodecyl sulfate, lactic acid, and hydroxyglutaric acid, and salts thereof, and the concentration of said substance in the measuring system being a concentration exhibiting the lactate dehydrogenase activity which does not affect the measurement of the alanine aminotransferase activity.