Journal of Applied Physiology, Vol 55, Issue 5 1536-1541, Copyright © 1983 by American Physiological Society
Platelets and leukocytes in the lungs after acute hypobaric hypoxia
G. Coates, C. Nahmias and A. Thind
To determine if decompression from sea level causes aggregation and
embolization of platelets or leukocytes to the lungs, we have measured the
accumulation of 51Cr-labeled platelets or 111In-labeled leukocytes in the
lungs of rabbits decompressed to 440 or 350 Torr for 18 or 40 h. To be
certain that any increased accumulation of labeled platelets (or
leukocytes) in the lungs was not just caused by an increased pulmonary
blood volume we also labeled the rabbits red blood cells with 59Fe. There
was no detectable accumulation of labeled platelets in the lungs on
decompression. In control animals there were 22 times as many labeled
leukocytes in the lungs as could be accounted for by the volume of blood in
the lungs. In experimental animals at 326 Torr for 18 h this figure was
reduced to 13.6. Hypobaric hypoxia caused an increase in circulating
granulocytes from a mean of 3.3 +/- 1.6 X 10(9)/l to 5.3 +/- 2.1 X 10(9)/l.
(P less than 0.005). Our results suggest that decompressions to 6,100 m for
18 h does not cause platelet sequestration in the lungs but does cause a
significant reduction in leukocytes in the lungs and a peripheral
granulocytosis.
