AJP - Heart and Circulatory Physiology, Vol 247, Issue 2 264-H272, Copyright © 1984 by American Physiological Society
Accumulation of nonesterified fatty acids in ischemic canine myocardium
F. W. Prinzen, G. J. Van der Vusse, T. Arts, T. H. Roemen, W. A. Coumans and R. S. Reneman
In ischemic myocardium the time course of nonesterified fatty acid (NEFA)
accumulation was studied in relation to changes in regional metabolism and
mechanics. In open-chest dogs a coronary artery was partially occluded for
120 min. In the ischemic myocardium no increase was observed in NEFA
content within 10 min, whereas changes were found in regional shortening,
high-energy phosphate content, and glucose arteriologcal venous difference.
During prolonged ischemia NEFA content increased, the highest values being
found in the inner and middle layers after 120 min (112 and 85 nmol X g-1,
respectively; control values 30); the value in the outer layers after 60
min was 93 nmol X g-1. After 120 min of ischemia, accumulation of NEFA
generally occurred when myocardial blood flow was below 0.3 ml X min-1 X
g-1 and ATP content was below 10 mumol X g dry wt-1. Under these
circumstances the individual NEFA with the highest relative increase was
arachidonic acid. The present findings indicate that the changes in
mechanical function and metabolism, as observed in myocardium rendered
ischemic for 10 min, are not caused by increased NEFA content and that NEFA
accumulation may partly result from hydrolysis of glycerophospholipids.
