|
|
||||||||
Department of Medical Physiology, Institute of Medical Biology, Faculty of Medicine, University of Tromsø, Norway
Submitted 19 September 2006 ; accepted in final form 6 January 2007
Hearts from type 2 diabetic (db/db) mice demonstrate altered substrate utilization with high rates of fatty acid oxidation, decreased functional recovery following ischemia, and reduced cardiac efficiency. Although db/db mice show overall insulin resistance in vivo, we recently reported that insulin induces a marked shift toward glucose oxidation in isolated perfused db/db hearts. We hypothesize that such a shift in metabolism should improve cardiac efficiency and consequently increase functional recovery following low-flow ischemia. Hearts from db/db and nondiabetic (db/+) mice were perfused with 0.7 mM palmitate plus either 5 mM glucose (G), 5 mM glucose and 300 µU/ml insulin (GI), or 33 mM glucose and 900 µU/ml insulin (HGHI). Substrate oxidation and postischemic recovery were only moderately affected by GI and HGHI in db/+ hearts. In contrast, GI and particularly HGHI markedly increased glucose oxidation and improved postischemic functional recovery in db/db hearts. Cardiac efficiency was significantly improved in db/db, but not in db/+ hearts, in the presence of HGHI. In conclusion, insulin and glucose normalize cardiac metabolism, restore efficiency, and improve postischemic recovery in type 2 diabetic mouse hearts. These findings may in part explain the beneficial effect of glucose-insulin-potassium therapy in diabetic patients with cardiac complications.
glucose; insulin; myocardial oxygen consumption; pressure-volume area
This article has been cited by other articles:
![]() |
M. Gandhi, B. A. Finegan, and A. S. Clanachan Role of glucose metabolism in the recovery of postischemic LV mechanical function: effects of insulin and other metabolic modulators Am J Physiol Heart Circ Physiol, June 1, 2008; 294(6): H2576 - H2586. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. F. du Toit, W. Smith, C. Muller, H. Strijdom, B. Stouthammer, A. J. Woodiwiss, G. R. Norton, and A. Lochner Myocardial susceptibility to ischemic-reperfusion injury in a prediabetic model of dietary-induced obesity Am J Physiol Heart Circ Physiol, May 1, 2008; 294(5): H2336 - H2343. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. D. Abel, S. E. Litwin, and G. Sweeney Cardiac Remodeling in Obesity Physiol Rev, April 1, 2008; 88(2): 389 - 419. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Boudina and E. D. Abel Diabetic Cardiomyopathy Revisited Circulation, June 26, 2007; 115(25): 3213 - 3223. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |