AJP - Heart and Circulatory Physiology, Vol 242, Issue 3 337-H348, Copyright © 1982 by American Physiological Society
Pulmonary and coronary endothelial effects of acute myocardial ischemia in dogs
M. H. Gee, J. T. Flynn and J. A. Spath Jr
We measured pulmonary arterial (Ppa) and left atrial (Pla) pressures, lung
lymph flow rate (QL), and protein clearance in 23 anesthetized dogs with
ligation (MI) dogs or sham ligation (sham-MI dogs) of a coronary artery
combined with either large transient increases in Pla or moderate
steady-state increases in Pla. In steady-state experiments we also
collected cardiac lymph. Plasma and lymph concentrations of several
prostanoids including prostacyclin (PGI2) and thromboxane B2 (TXB2) were
measured. Lung lymph flow rates and protein clearances were increased in MI
dogs compared with those in sham-MI dogs in experiments with transient
increases in Pla. Similarly in steady-state experiments lung QL and protein
clearance were increased after MI. Cardiac QL increased after MI with no
change in lymph protein clearance. Lung and cardiac lymph PGI2 and plasma
TXB2 concentrations increased after MI. We suggest that acute MI results in
increased lung vascular permeability and that activation of formed elements
in blood may be involved in mediating MI-induced vascular injury.
