Abstract
1. A modification of the methods of Miller and of Schimassek for the perfusion of the isolated rat liver, suitable for the study of gluconeogenesis, is described. 2. The main modifications concern the operative technique (reducing the period of anoxia during the operation to 3min.) and the use of aged (non-glycolysing) red cells in the semi-synthetic perfusion medium. 3. The performance of the perfused liver was tested by measuring the rate of gluconeogenesis, of urea synthesis and the stability of adenine nucleotides. Higher rates of gluconeogenesis (1μmole/min./g.) from excess of lactate and of urea synthesis from excess of ammonia (4μmoles/min./g. in the presence of ornithine) were observed than are likely to occur in vivo where rates are limited by the rate of supply of precursor. The concentrations of the three adenine nucleotides in the liver tissue were maintained within 15% over a perfusion period of 135min. 4. Ca2+, Na+, K+, Mg2+ and phosphate were found to be required at physiological concentrations for optimum gluconeogenesis but bicarbonate and carbon dioxide could be largely replaced by phosphate buffer without affecting the rate of gluconeogenesis. 5. Maximal gluconeogenesis did not decrease maximal urea synthesis in the presence of ornithine and ammonia and vice versa. This indicates that the energy requirements were not limiting the rates of gluconeogenesis or of urea synthesis. 6. Addition of lactate, and especially ammonium salts, increased the uptake of oxygen more than expected on the basis of the ATP requirements of the gluconeogenesis and urea synthesis.
Full text
PDF








Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- BISHOP J. M. The measurement of blood gas tensions; measurement of blood oxygen tension. Proc R Soc Med. 1960 Mar;53:177–180. doi: 10.1177/003591576005300304. [DOI] [PMC free article] [PubMed] [Google Scholar]
- GALE E. F. MECHANISMS OF ANTIBIOTIC ACTION. Pharmacol Rev. 1963 Sep;15:481–530. [PubMed] [Google Scholar]
- Gevers W., Krebs H. A. The effects of adenine nucleotides on carbohydrate metabolism in pigeon-liver homogenates. Biochem J. 1966 Mar;98(3):720–735. doi: 10.1042/bj0980720. [DOI] [PMC free article] [PubMed] [Google Scholar]
- HORNBROOK K. R., BURCH H. B., LOWRY O. H. CHANGES IN SUBSTRATE LEVELS IN LIVER DURING GLYCOGEN SYNTHESIS INDUCED BY LACTATE AND HYDROCORTISONE. Biochem Biophys Res Commun. 1965 Jan 18;18:206–211. doi: 10.1016/0006-291x(65)90741-2. [DOI] [PubMed] [Google Scholar]
- KREBS H. A., BENNETT D. A., DE GASQUET P., GASQUET P., GASCOYNE T., YOSHIDA T. Renal gluconeogenesis. The effect of diet on the gluconeogenic capacity of rat-kidney-cortex slices. Biochem J. 1963 Jan;86:22–27. doi: 10.1042/bj0860022. [DOI] [PMC free article] [PubMed] [Google Scholar]
- KREBS H. A. Body size and tissue respiration. Biochim Biophys Acta. 1950 Jan;4(1-3):249–269. doi: 10.1016/0006-3002(50)90032-1. [DOI] [PubMed] [Google Scholar]
- Krebs H. A., Dierks C., Gascoyne T. Carbohydrate synthesis from lactate in pigeon-liver homogenate. Biochem J. 1964 Oct;93(1):112–121. doi: 10.1042/bj0930112. [DOI] [PMC free article] [PubMed] [Google Scholar]
- LOWRY O. H., PASSONNEAU J. V., HASSELBERGER F. X., SCHULZ D. W. EFFECT OF ISCHEMIA ON KNOWN SUBSTRATES AND COFACTORS OF THE GLYCOLYTIC PATHWAY IN BRAIN. J Biol Chem. 1964 Jan;239:18–30. [PubMed] [Google Scholar]
- MILLER L. L., BLY C. G., WATSON M. L., BALE W. F. The dominant role of the liver in plasma protein synthesis; a direct study of the isolated perfused rat liver with the aid of lysine-epsilon-C14. J Exp Med. 1951 Nov;94(5):431–453. doi: 10.1084/jem.94.5.431. [DOI] [PMC free article] [PubMed] [Google Scholar]
- MORTIMORE G. E. Effect of insulin on potassium transfer in isolated rat liver. Am J Physiol. 1961 Jun;200:1315–1319. doi: 10.1152/ajplegacy.1961.200.6.1315. [DOI] [PubMed] [Google Scholar]
- SCHIMASSEK H., MITZKAT H. J. UBER EINE SPEZIFISCHE WIRKUNG DES GLUCAGON AUF DIE EMBDEN-MEYERHOF-KETTE IN DER LEBER. VERSUCHE AN DER ISOLIERT PERFUNDIERTEN RATTENLEBER. Biochem Z. 1963 Aug 14;337:510–518. [PubMed] [Google Scholar]
- SCHIMASSEK H. [Metabolites of carbohydrate metabolism in the isolated perfused rat liver]. Biochem Z. 1963;336:460–467. [PubMed] [Google Scholar]
- SCHIMKE R. T. Adaptive characteristics of urea cycle enzymes in the rat. J Biol Chem. 1962 Feb;237:459–468. [PubMed] [Google Scholar]
- SCHIMKE R. T. Differential effects of fasting and protein-free diets on levels of urea cycle enzymes in rat liver. J Biol Chem. 1962 Jun;237:1921–1924. [PubMed] [Google Scholar]
- SCHMIDT-THOME J., MAGER A., SCHOENE H. H. [On the chemistry of a new plasma expander]. Arzneimittelforschung. 1962 Apr;12:378–380. [PubMed] [Google Scholar]
- Struck E., Ashmore J., Wieland O. Stimulierung der Gluconeogenese durch langkettige Fettsäuren und Glucagon. Biochem Z. 1965 Nov 5;343(1):107–110. [PubMed] [Google Scholar]
- Trowell O. A. Urea formation in the isolated perfused liver of the rat. J Physiol. 1942 Mar 31;100(4):432–458. doi: 10.1113/jphysiol.1942.sp003954. [DOI] [PMC free article] [PubMed] [Google Scholar]
- WOLLENBERGER A., RISTAU O., SCHOFFA G. [A simple technic for extremely rapid freezing of large pieces of tissue]. Pflugers Arch Gesamte Physiol Menschen Tiere. 1960;270:399–412. [PubMed] [Google Scholar]
