Utilization of energy-providing substrates in the isolated working rat heart
- 15 March 1980
- journal article
- research article
- Published by Portland Press Ltd. in Biochemical Journal
- Vol. 186 (3), 701-711
- https://doi.org/10.1042/bj1860701
Abstract
1. An improved perfusion system for the isolated rat heart is described. It is based on the isolated working heart of Neely, Liebermeister, Battersby & Morgan (1967) (Am. J. Physiol. 212, 804-814) and allows the measurement of metabolic rates and cardiac performance at a near-physiological workload. The main improvements concern better oxygenation of the perfusion medium and greater versatility of the apparatus. Near-physiological performance (cardiac output and aortic pressure) was maintained for nearly 2 h as compared with 30 min or less in the preparations of earlier work. 2. The rates of energy release (O2 uptake and substrate utilization) were 40-100% higher than those obtained by previous investigators, who used hearts at subphysiological workloads. 3. Values are given for the rates of utilization of glucose, lactate, oleate, acetate and ketone bodies, for O2 consumption and for the relative contributions of various fuels to the energy supply of the heart. Glucose can be replaced to a large extent by lactate, oleate or acetate, but not by ketone bodies. 4. Apart from quantitative differences there were also major qualitative differences between the present and previous preparations. Thus insulin was not required for maximal rates of glucose consumption at near-physiological, in contrast with subphysiological, workloads when glucose was the sole added substrate. When glucose oxidation was suppressed by the addition of other oxidizable substrates (lactate, acetate or acetoacetate), insulin increased the contribution of glucose as fuel for cardiac energy production at high workload. 5. In view of the major effects of workload on cardiac metabolism, experimentation on hearts performing subphysiologically or unphysiologically is of limited value to the situation in vivo.This publication has 29 references indexed in Scilit:
- How to quantify pump function of the heart. The value of variables derived from measurements on isolated muscle.Circulation Research, 1979
- Control of maximum rates of glycolysis in rat cardiac muscle.Circulation Research, 1979
- Effects of lactation of ketogenesis from oleate or butyrate in rat hepatocytesBiochemical Journal, 1977
- Labeling of RNA in the perfused heart: The problem of bacterial contaminationBiochimica et Biophysica Acta (BBA) - Nucleic Acids and Protein Synthesis, 1969
- Gluconeogenesis in the perfused rat liverBiochemical Journal, 1966
- GLYCOLYTIC CONTROL MECHANISMS .I. INHIBITION OF GLYCOLYSIS BY ACETATE AND PYRUVATE IN ISOLATED PERFUSED RAT HEART1965
- Regulation of glucose uptake by muscles. 10. Effects of alloxan-diabetes, starvation, hypophysectomy and adrenalectomy, and of fatty acids, ketone bodies and pyruvate, on the glycerol output and concentrations of free fatty acids, long-chain fatty acyl-coenzyme A, glycerol phosphate and citrate-cycle intermediates in rat heart and diaphragm musclesBiochemical Journal, 1964
- Effects of insulin and starvation on the metabolism of acetate and pyruvate by the perfused rat heartBiochemical Journal, 1964
- Interrelation between carbohydrate and fatty acid metabolism of isolated perfused rat heartMetabolism, 1964
- Effects of insulin and diet on the metabolism of l(+)-lactate and glucose by the perfused rat heartBiochemical Journal, 1962