Glucose utilization and glycogen turnover are accelerated in hypertrophied rat hearts during severe low-flow ischemia.

Abstract We undertook this study to determine if the metabolism of exogenous glucose and glycogen in hypertrophied hearts differed from that in normal hearts during severe ischemia. Thus, rates of glycolysis ( 3 H 2 O production) and oxidation ( 14 CO 2 production) from exogenous glucose and glycogen were measured in isolated working control ( n =13) and hypertrophied ( n =12) hearts from sham-operated and aortic-banded rats during 40 min of severe low-flow ischemia. Hearts, in which glycogen was prelabelled with [5- 3 H]- or [ 14 C]-glucose, were paced and perfused with Krebs–Henseleit solution containing 1.2 m m palmitate, 5.5 m m [5- 3 H]- or [ 14 C]-glucose (different from the isotope used to label glycogen), 0.5 m m lactate and 100 μ U/ml insulin during ischemia. Rates of glycolysis from exogenous glucose (3301±122 v 2467±167 nmol/min/g dry wt, mean± s.e.m P v 725±21 nmol/min/g dry wt, P v 140±9 nmol/min/g dry wt, P