Liver and Bile

Abstract

Chicago, Illinois 169Annu. Rev. Physiol. 1946.8:169-198. Downloaded from www.annualreviews.org Access provided by Michigan State University Library on 02/03/15. For personal use only.Quick links to online content Further ANNUAL REVIEWS Annu. Rev. Physiol. 1946.8:169-198. Downloaded from www.annualreviews.org Access provided by Michigan State University Library on 02/03/15. For personal use only.LIVER AND BILE 171 carbon was recovered in the expired air in a sixteen hour period. The distribution of the nitrogen of glycine was followed byShemin & Rittenberg (10), who fed the heavy nitrogen as glycine to rats and followed its concentration in various tissue proteins.Their results indicate that half the total protein nitrogen of the liver is replaced every seven days, and that 10 per cent of the liver glycine nitrogen is replaced daily by glycine from other sources.Treadwell, Tidwell & Grafa (11) found that rats maintained on a high fat, low protein diet had a significantly higher liver glycogen than when the diet was high in both fat and protein.The animals with fatty livers (low protein) had an increased glycogenolysis during fasting and decreased glycogenesis following glucose administration. Soskin (12) has recently reviewed the general role of the liver in regulating the blood sugar level and emphasized the diabetic type of sugar tolerance curve associated with impaired liver function.The hepatic reserve of glycogen in children has been estimated by Mirsky & Nelson (13) by determining the sugar excretion, hypoglycemia, and ketosis provoked by phlorhizin administration.A loss of 15 to 20 gm. of sugar by a normal child leads to hypo glycemia_and ketonemia. Younger children were found to have less glycogen reserve. Dziewiatkowski & Lewis (14) found that glycogen depletion occurs in young well-fed rats four hours after administration of menthol or sodium tertiary butyl acetate. Since these compounds are excreted as glycuronates, it appears probable that glycogen is used as a source for glycuronate syn thesis. This relation between glycuronates and glycogen may account for the results reported by Ottenberg and collaborators (15), who found a low glycuronate excretion after borneol ad ministration, not only by patients with liver disease but by patients with other diseases as well.Other aspects of liver metabolism.-Dounce has described an improved method for isolating the intact cell nuclei of rat liver (16). The following enzymes were found in the nuclei: arginase, cytochrome oxidase, esterase, lactic acid dehydrogenase, alkaline and acid phosphatase. The total lipid content of the nuclei was between 10.5 and 11.0 per cent. A heat labile enzyme that cata lyzes the decarboxylation of oxalacetic acid was shown by Evans and associates (17) to be present in a c�ll-free extract of pigeon liver. WQQdwa r q (18) found that liver tumors produced by Annu. Rev. Physiol. 1946.8:169-198. Downloaded from www.annualreviews.org Access provided by Michigan State University Library on 02/03/15. For personal use only.