Neutrophil recruitment as a factor limiting injury or promoting recovery from acute lung injury.
We studied 1) neutrophil mobilization in sheep given endotoxin (10 ng.kg-1.min-1, n = 5) for 4 h, 2) surviving (n = 17) and nonsurviving sheep (n = 8) during a 12-h infusion of endotoxin, and 3) adult sheep (n = 8) or lambs (n = 8) infused with endotoxin for 12 h. Bone marrow cells of sheep declined from a baseline value of 10,533 +/- 1,784 to 5,966 +/- 1,980 cells/microliter (P < 0.05) 4 h after endotoxin. After 12 h of endotoxin infusion, circulating neutrophils remained reduced from baseline values of 2,000-4,000 cells/microliter to 343 +/- 70 in lambs and 484 +/- 236 in nonsurviving sheep, while beginning to recover in surviving sheep to 1,838 +/- 467 cells/microliter. In lambs and nonsurviving sheep, a 12-h infusion of endotoxin increased lung lymph protein clearance tenfold compared with a fivefold increase in surviving sheep. Neutrophils cultured from sheep bone marrow exposed to lamb postendotoxin plasma failed to increase in cell number (609 +/- 229 to 610 +/- 182 cells/microliter), whereas similar cells exposed to adult sheep postendotoxic plasma showed a significant increase in cell number (1,069 +/- 101 to 2,293 +/- 448 cells/microliter, P < 0.05). Our results are consistent with the hypothesis that the ability to recruit neutrophils to the circulation during periods of inflammation is important in limiting the severity of acute lung injury.
Carey
L A
LA
Department of Physiology, Jefferson Medical College, Thomas Jefferson University, Philadelphia 19107, USA.
Perkowski
S Z
SZ
Lipsky
C L
CL
Cirelli
R A
RA
Spath
J A
JA
Gee
M H
MH
D000208:Acute Disease; D000818:Animals; D001773:Blood Cells / Q000473:pathology; D001853:Bone Marrow / Q000473:pathology; D002452:Cell Count; D002465:Cell Movement; D004731:Endotoxins; D005260:Female; D006439:Hemodynamics; D007962:Leukocytes / Q000473:pathology; D008168:Lung / Q000378:metabolism; D008171:Lung Diseases / Q000139:chemically induced / Q000473:pathology / Q000503:physiopathology*; D008196:Lymph / Q000378:metabolism; D008297:Male; D009504:Neutrophils / Q000502:physiology*; D011506:Proteins / Q000378:metabolism
D004731:Endotoxins; D011506:Proteins