Journal of Applied Physiology, Vol 60, Issue 4 1186-1189, Copyright © 1986 by American Physiological Society
Partial recovery of neutrophil functions during prolonged hypothermia in pigs
W. D. Biggar, C. Barker, D. Bohn and G. Kent
The changes in circulation and migration of mature and immature neutrophils
during 12 h of hypothermia have been studied using an experimental pig
model. At 29 degrees C the number of circulating neutrophils fell from 5
+/- 1.1 at 37 degrees C to 3.5 +/- 0.6 X 10(9)/l and then remained
unchanged while hypothermia was maintained. The number of circulating
immature neutrophils did not fall during hypothermia. During hypothermia,
hydrocortisone failed to stimulate the release of mature and immature
neutrophils from the bone marrow. In contrast, endotoxin caused a profound
neutropenia followed by a gradual increase in the number of circulating
mature neutrophils, which by 6 h, was similar to the number circulating
before endotoxin administration. At 29 degrees C the number of circulating
immature neutrophils also fell following endotoxin but then increased over
the number circulating before endotoxin administration by approximately
10-fold. Compared with neutrophil migration at 37 degrees C, very few
mature or immature neutrophils migrated to an inflammatory site during the
12 h of hypothermia (29 degrees C). Unlike hypothermia in vitro, where
neutrophil function may improve with time in vivo, neutrophil function
remains compromised.
