Relation of Body-weight to Hepatic Glutamic Pyruvic Transaminase Activity

Abstract

KLEIBER^1,2 first reported in 1932 the concept that a linear relation exists between the logarithms of metabolic rate and, body-weight. The basal rate of oxygen consumption per gram of body-weight was found to be proportional to an exponential function of the body-weight (oxygen consumption × weight^−3/4 = constant)³. More recent observations have suggested that this correlation of body-weight and metabolic rate can be extended to the concentration of specific oxidative enzymes. Total body content and contents in various mammalian organs of cytochrome oxidase⁴, homogentisic oxidaso and p-hydroxy-phenyl-pyruvate oxidase⁵ have been observed to be related to the body-weight by this same mathematical expression¹. Since the logarithm of the total body enzyme activity (E)/g body-weight is linearly related to the logarithm of the body-weight, a weight parity expression has been used for comparing enzyme activities in animals with different weights by Lin et al.⁵, where c and k are determined from the intercept and slope: (E × W^k = c). Investigators of small laboratory animals weighing up to 4 kg have revealed that certain transaminases (tyrosine-α-ketoglutarate and phenylalanine-pyruvate) are related to different power functions of the body-weight than those observed with the oxidative enzymes.