Hypoxemia modifies circulating and exudate neutrophil number and functional responses in carrageenin-induced pleurisy in the rat.
To assess the effect of hypoxemia on the responses of polymorphonuclear neutrophils (PMN) during an inflammatory response, rats were maintained in a low F1O2 atmosphere (9% O2) or room air for 12 h before intrathoracic injection of carrageenin or intradermal injections of agonists. After 4 h, hypoxemic rats had 50% more circulating PMN in blood and 25% less PMN in pleural exudate, whereas the number of PMN in skin biopsies did not differ from controls. Following hypoxemia, basal adhesion of blood PMN to serum-coated plastic wells was unchanged, whereas fMLP-stimulated adhesion was 50% greater. In contrast, basal adhesion of exudate PMN was 72% greater. In hypoxemic rats, exudate PMN produced 64% more PMA-stimulated superoxide than blood PMN; furthermore, blood and exudate PMN produced 4.5- and 2-fold more LPS-stimulated nitric oxide than controls, respectively. These results show that a moderate level of hypoxemia may trigger mechanisms that will interfere with PMN emigration yet prime these cells for enhanced responses upon stimulation.
Tremblay
P B
PB
Faculty of Pharmacy, Université de Montréal, Québec, Canada.
Macari
D M
DM
Martel
D
D
du Souich
P
P
Barja-Fidalgo
C
C
Marleau
S
S
D000818:Animals; D002351:Carrageenan; D000860:Hypoxia / Q000097:blood / Q000276:immunology*; D007958:Leukocyte Count; D008070:Lipopolysaccharides / Q000494:pharmacology; D008297:Male; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000494:pharmacology; D009504:Neutrophils / Q000166:cytology / Q000187:drug effects / Q000276:immunology*; D009573:Nitrites / Q000378:metabolism; D010998:Pleurisy / Q000097:blood / Q000139:chemically induced / Q000276:immunology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013481:Superoxides / Q000378:metabolism
D008070:Lipopolysaccharides; D009573:Nitrites; D013481:Superoxides; D009240:N-Formylmethionine Leucyl-Phenylalanine; D002351:Carrageenan