Influence of precursors of biosyntheses on the energy metabolism of the liver cell - PubMed (original) (raw)
- PMID: 6312977
Influence of precursors of biosyntheses on the energy metabolism of the liver cell
G Letko et al. Biomed Biochim Acta. 1983.
Abstract
The influence of variable energy demand on both the total ATP/ADP ratio and the rate of respiration was investigated in isolated hepatocytes. For hepatocytes respiring at the same rate, different ATP/ADP ratios were observed when the energy drain was caused either by ureogenesis and gluconeogenesis or by partial uncoupling. These differences were provoked by an additional effect of the precursors of syntheses studied, i.e. lactate or ornithine, on the hydrogen supply of the respiratory chain, as was reflected in terms of the reduction degree of cytochrome c in isolated mitochondria. For a fixed hydrogen supply there exists a defined characteristic ATP/ADP ratio versus rate of respiration. It is concluded that the respiratory rate, the mitochondrial redox state and the phosphorylation potential (transmitted into the extramitochondrial one by the adenine nucleotide translocator) represent a system of three interdependent parameters. The presence of metabolic precursors such as ornithine and lactate enhances the load of the cellular energy metabolism as well as the energy supply of the cell, the latter through improvement of substrate utilization. The ambivalent character of the precursors makes possible a kind of forward optimization of the hepatic energy metabolism which allows the cell to perform syntheses at a relatively high ATP/ADP ratio and, unless syntheses take place, to save energy by avoiding higher ATP/ADP ratios.
Similar articles
- Interrelationship between oxidative energy transformation and energy consumption at mitochondrial and cellular levels.
Letko G, Küster U, Bohnensack R, Böhme G, Pohl K, Kunz W. Letko G, et al. Acta Biol Med Ger. 1982;41(9):735-50. Acta Biol Med Ger. 1982. PMID: 6299035 - Interrelationships between hydrogen-supplying reactions, respiration rate and extramitochondrial adenine nucleotide pattern.
Böhme G, Schönfeld P, Bohnensack R, Küster U, Kunz W. Böhme G, et al. Physiol Bohemoslov. 1982;31(2):159-68. Physiol Bohemoslov. 1982. PMID: 6212956 - Control mechanisms of energy-dependent metabolic pathways in hepatocytes.
Tager JM, Wanders RJ, Groen AK, van der Meer R, Akerboom TP, Meijer AJ. Tager JM, et al. Acta Biol Med Ger. 1981;40(7-8):895-906. Acta Biol Med Ger. 1981. PMID: 7036612 Review. - Mitochondrial energetic metabolism-some general principles.
Mazat JP, Ransac S, Heiske M, Devin A, Rigoulet M. Mazat JP, et al. IUBMB Life. 2013 Mar;65(3):171-9. doi: 10.1002/iub.1138. IUBMB Life. 2013. PMID: 23441039 Review.
Cited by
- Control of respiration and ATP synthesis in mammalian mitochondria and cells.
Brown GC. Brown GC. Biochem J. 1992 May 15;284 ( Pt 1)(Pt 1):1-13. doi: 10.1042/bj2840001. Biochem J. 1992. PMID: 1599389 Free PMC article. Review.