Fibronectin levels in plasma after platelet-activating factor inhalation.
We evaluated fibronectin levels in plasma and blood leukocyte counts after platelet-activating factor-acether (PAF) inhalation to examine whether PAF may cause pulmonary vascular injury. PAF inhalation challenges were performed on 5 normal subjects and 5 atopic asthmatics. Fibronectin levels in plasma were significantly increased at 5 min (342.5 +/- 36.9 micrograms/ml) after PAF challenge as compared with the baseline values of 277.1 +/- 33.0 micrograms/ml (p less than 0.024). Total white blood cell and neutrophil counts were significantly decreased 5 min after PAF inhalation (WBC from 5,360 +/- 460 to 4,260 +/- 380/mm3, p less than 0.028; neutrophils from 3,113 +/- 441 to 2,214 +/- 344/mm3, p less than 0.043). Our study shows that plasma fibronectin levels transiently increase and that peripheral total WBC counts decrease after PAF inhalation. Elevated fibronectin levels may provide evidence of pulmonary vascular injury due to neutrophils which might be primed and recruited to pulmonary circulation by PAF.
Nabe
M
M
Allergic Disease Center, Creighton University School of Medicine, Omaha, Nebr.
Miyagawa
H
H
Hopp
R J
RJ
Agrawal
D K
DK
Bewtra
A K
AK
Townley
R G
RG
D000280:Administration, Inhalation; D000328:Adult; D005260:Female; D005353:Fibronectins / Q000097:blood*; D006801:Humans; D007958:Leukocyte Count; D008168:Lung / Q000187:drug effects; D008297:Male; D008875:Middle Aged; D009504:Neutrophils / Q000187:drug effects; D010972:Platelet Activating Factor / Q000633:toxicity*
D005353:Fibronectins; D010972:Platelet Activating Factor