Glucagon stimulates ketone utilization by rat brain slices.
- 29 February 1984
- journal article
- research article
- Published by Wolters Kluwer Health in Stroke
- Vol. 15 (2), 324-328
- https://doi.org/10.1161/01.str.15.2.324
Abstract
Glucagon has been shown previously to increase further the enhanced tolerance for hypoxia observed in mice with elevated blood ketones. Glucagon is also known to increase blood glucose and to alter directly the metabolism of some (liver) cells. Both the increase in blood glucose and altered cellular metabolism could contribute to the increase in tolerance for hypoxia observed in mice given glucagon in combination with the ketone, beta-hydroxybutyrate. To evaluate the systemic component of this hypothesis, blood glucose, beta-hydroxybutyrate, and glucagon were elevated alone or simultaneously and hypoxic tolerance of mice was measured. To identify possible cellular effects of glucagon on glucose or ketone metabolism, we measured the incorporation of radiolabeled glucose or beta-hydroxybutyrate into CO2 or total lipid in isolated rat brain slices. Both glucagon and glucose increased hypoxic tolerance of ketotic mice but our data do not support the hypothesis that glucagon's action was only through an elevation of blood glucose. In brain slices glucagon stimulated the incorporation of beta-hydroxybutyrate into CO2 both in the presence or absence of additional glucose. These results demonstrate that glucagon has a direct effect on brain metabolism which may contribute to the increased tolerance for hypoxia. They, however, do not exclude the possibility that glucagon is working in addition to increase hypoxic survival in ketotic mice by increasing the availability of glucose to the brain.This publication has 12 references indexed in Scilit:
- A re-examination of physostigmine-induced cerebral protection in the hypoxic mouse. A critical assessment of the model.Stroke, 1980
- Ketone Bodies Are Selectively Used by Individual Brain RegionsScience, 1979
- Glucagon and diabetes: A reappraisalDiabetologia, 1979
- Isolated hepatocytes as a model for the study of stable glucagon effects on mitochondrial respiratory functionsFEBS Letters, 1979
- Regulation of glucose and ketone-body metabolism in brain of anaesthetized ratsBiochemical Journal, 1974
- D-(–)-3-HydroxybutyratePublished by Elsevier ,1974
- Metabolic interactions of glucose, lactate, and beta-hydroxybutyrate in rat brain slicesAmerican Journal of Physiology-Legacy Content, 1969
- Brain Metabolism during Fasting*JCI Insight, 1967
- The Hypoglycemic Action of Ketones. II. Evidence for a Stimulatory Feedback of Ketones on the Pancreatic Beta Cells *JCI Insight, 1964
- Studies in fat metabolismBiochemical Journal, 1935