Glycogen Metabolism in the Aerobic Hypertrophied Rat Heart

Author:

Allard Michael F.1,Henning Sarah L.1,Wambolt Richard B.1,Granleese Shaun R.1,English Dean R.1,Lopaschuk Gary D.1

Affiliation:

1. From the Cardiovascular Research Laboratory, University of British Columbia, Vancouver (M.F.A., S.L.H., R.B.W., S.R.G., D.R.E.), and the Cardiovascular Disease Research Group, University of Alberta, Edmonton (G.D.L.), Canada.

Abstract

Background Rates of glycolysis from exogenous glucose are accelerated in hypertrophied hearts. In this study, we determined whether alterations in the metabolism of glycogen, an endogenous storage form of glucose, also occur in hypertrophied hearts. Methods and Results Rates of glycolysis ([ 3 H]H 2 O production) and oxidation ([ 14 C]CO 2 production) from exogenous glucose and glycogen were measured in isolated working hearts from control and aortic-banded rats. Hearts in which glycogen was prelabeled with [5- 3 H]- or [U- 14 C]glucose were perfused with buffer containing 11 mmol/L [5- 3 H]- or [U- 14 C]glucose (different from the isotope used to prelabel glycogen), 0.4 mmol/L palmitate, 0.5 mmol/L lactate, and 100 μU/mL insulin. Rates of glycolysis from exogenous glucose were greater (3471±114 versus 2665±194 nmol glucose·min −1 ·g dry wt −1 , P <.05, n=4 to 6, mean±SEM) and rates of exogenous glucose oxidation (445±36 versus 619±16 nmol glucose·min −1 ·g dry wt −1 , P <.05, n=4 to 6) were lower in hypertrophied hearts than in control hearts. Rates of glycolysis and oxidation from glycogen were not different between hypertrophied and control hearts. A greater proportion of glycogen was oxidized (80% to 100%) than the proportion of exogenous glucose oxidized (13% to 24%) in both groups. Additionally, 10.5±1.4 and 12.3±1.0 μmol/g dry wt of glycogen was synthesized in hypertrophied and control hearts, respectively, indicating that simultaneous synthesis and degradation (ie, glycogen turnover) occurred in both groups. Conclusions Thus, aerobic myocardial glycogen metabolism in the hypertrophied heart is similar to that observed in the normal heart even though exogenous glucose metabolism is altered in the hypertrophied heart.

Publisher

Ovid Technologies (Wolters Kluwer Health)

Subject

Physiology (medical),Cardiology and Cardiovascular Medicine

Cited by 55 articles. 订阅此论文施引文献 订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3