Journal of Applied Physiology, Vol 65, Issue 2 617-624, Copyright © 1988 by American Physiological Society
Effects of coronary ischemia on lung fluid balance in conscious sheep
T. Toyofuku, T. Kobayashi, K. Kubo, S. Koyama and S. Kusama
First Department of Internal Medicine, Shinshu University School of Medicine, Matsumoto, Japan.
It has been suggested that coronary ischemia increases extravascular lung
water. To determine whether pulmonary microvascular permeability is
increased by coronary ischemia, we measured pulmonary hemodynamics, lung
lymph flow (QL), and lymph-to-plasma protein concentration ratio (L/P) in
12 sheep with chronic lung lymph fistulas. Studies were done in 3 groups:
in group 1 (n = 7) a marginal branch of the left circumflex artery (Lcx)
was occluded, in group 2 (n = 5) left atrial pressure (Pla) was
mechanically raised by 10 mmHg, and in group 3 (n = 5) Lcx was occluded and
Pla was raised by 10 mmHg. In group 1, coronary occlusion increased QL (4.6
+/- 0.4 to 8.3 +/- 2.6 ml/h) without changes in L/P. In group 2, elevated
Pla increased QL (5.1 +/- 1.2 to 10.1 +/- 3.0 ml/h) with decreases in L/P
(0.71 +/- 0.02 to 0.61 +/- 0.02). In group 3, coronary occlusion with
elevated Pla caused a further increase in QL (5.0 +/- 1.5 to 16.9 +/- 4.6
ml/h) without significant decreases in L/P (0.71 +/- 0.01 to 0.65 +/-
0.06). Lung lymph concentrations of 6-keto-prostaglandin F1 alpha (a
degradation product of prostacyclin) increased transiently after coronary
occlusion. These results indicate that coronary occlusion can increase
transcapillary protein transport in lungs of conscious sheep and
simultaneously increase prostacyclin production in the lung.
