Brand M D, Couture P, Else P L, Withers K W, Hulbert A J
Department of Biology, University of Wollongong, New South Wales, Australia.
Biochem J. 1991 Apr 1;275 ( Pt 1)(Pt 1):81-6. doi: 10.1042/bj2750081.
Standard metabolic rate is 7-fold greater in the rat (a typical mammal) than in the bearded dragon, Amphibolurus vitticeps (a reptile with the same body mass and temperature). Rat hepatocytes respire 4-fold faster than do hepatocytes from the lizard. The inner membrane of isolated rat liver mitochondrial has a proton permeability that is 4-5-fold greater than the proton permeability of the lizard liver mitochondrial membrane per mg of mitochondrial protein. The greater permeability of rat mitochondria is not caused by differences in the surface area of the mitochondrial inner membrane, but differences in the fatty acid composition of the mitochondrial phospholipids may be involved in the permeability differences. Greater proton permeability of the mitochondrial inner membrane may contribute to the greater standard metabolic rate of mammals.
标准代谢率在大鼠（一种典型的哺乳动物）中比在髯狮蜥（Amphibolurus vitticeps，一种与大鼠体重和体温相同的爬行动物）中高7倍。大鼠肝细胞的呼吸速度比蜥蜴肝细胞快4倍。分离的大鼠肝脏线粒体的内膜质子通透性比蜥蜴肝脏线粒体膜每毫克线粒体蛋白的质子通透性大4至5倍。大鼠线粒体较大的通透性并非由线粒体内膜表面积的差异引起，但线粒体磷脂脂肪酸组成的差异可能与通透性差异有关。线粒体内膜较高的质子通透性可能导致哺乳动物具有较高的标准代谢率。
