© 1995 by European Society of Cardiology
Copyright © 1995, European Society of Cardiology
Effects of chronic right ventricular pressure overload on myocardial glucose and free fatty acid metabolism in the conscious rat
aFirst Department of Internal Medicine, Tohoku University School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai 980, Japan
bDivision of Radiopharmaceutical Research, Cyclotron and Radioisotope Centre, Tohoku University, Sendai 980, Japan
* Correspondence to Dr Ishide.
Objective: The aim was to investigate the effects of chronic right ventricular pressure overload on myocardial glucose and free fatty acid metabolism in the right ventricular free wall, ventricular septum, and left ventricular free wall. Methods: Using a glucose analogue, 14C-2-deoxyglucose (14C-DG), and a fatty acid analogue, 14C-β methylheptadecanoic acid (14C-BMHDA), quantitative autoradiography was performed in conscious rats with 4 week pulmonary artery constriction. Results: In rats with chronic pulmonary artery constriction, right ventricular peak systolic pressure and right ventricular weight to body weight ratio increased by 88% and 127%, respectively, compared with sham operated rats (P < 0.01 for each). In the right ventricular free wall, 14C-DG deposition increased but 14C-BMHDA accumulation did not differ in the chronic pulmonary artery constricted rats compared with sham operated rats [212(SEM 27), n = 6
101(15) nCi·g–1, n = 4, P < 0.01, and 406(40), n = 6,
333(48) nCi·g–1, n = 4, NS, respectively]. In sham operated rats, 14C-DG and 14C-BMHDA deposition did not differ between the ventricular septum and the left ventricular free wall. In contrast, 14C-DG and 14C-BMHDA accumulations were lower in the ventricular septum compared with the left ventricular free wall wall in chronic pulmonary artery constricted rats. Myocardial blood flow assessed by 14C-iodoantipyrine was homogeneously distributed throughout both ventricles. Conclusions: Chronic right ventricular pressure overload increases myocardial glucose uptake and/or its phosphorylation in the right ventricular free wall, and alters the regional profiles of substrate use in the ventricular septum and left ventricular free wall despite the homogeneous blood flow distribution. The results of the acute right ventricular pressure overload study, in which only right ventricular 14C-BMHDA deposition was increased compared with controls, suggest that the findings obtained from chronic pulmonary artery constricted rats cannot be explained by increased right ventricular pressure alone.
KEYWORDS glucose; free fatty acids; metabolism; autoradiography; right ventricular hypertrophy
This study was supported in part by a grant-in-aid (62624006) from the Ministry of Science, Education, and Culture of Japan.
![]()
CiteULike
Connotea
Del.icio.us What's this?
This article has been cited by other articles:
![]() |
H. C. Champion, E. D. Michelakis, and P. M. Hassoun Comprehensive Invasive and Noninvasive Approach to the Right Ventricle-Pulmonary Circulation Unit: State of the Art and Clinical and Research Implications Circulation, September 15, 2009; 120(11): 992 - 1007. [Full Text] [PDF] |
||||
