Increased pulmonary production of immunoreactive 15-hydroxyeicosatetraenoic acid in an animal model of asthma.
Airway obstruction and hyperreactivity are characteristics of human asthma and of "heaves," a naturally occurring respiratory disorder of horses and ponies. We measured pulmonary function and plasma immunoreactive 15-hydroxyeicosatetraenoic acid (i15-HETE) concentrations in simultaneously collected carotid artery and right ventricle blood samples in five affected ponies and their age- and gender-matched control ponies. Measurements and sampling were performed before (Period A), during (Period B), and following recovery from (Period C) acute airway obstruction precipitated by housing ponies in a barn and exposing them to hay dust. Pulmonary resistance increased significantly, and dynamic compliance and PaO2 decreased significantly in affected ponies at Period B. Plasma i15-HETE concentrations were greater in carotid artery samples compared with right ventricle samples in affected ponies at each measurement period, suggesting that the lung was a source of i15-HETE. Carotid artery i15-HETE concentrations were significantly greater in affected ponies than in control ponies and increased at Period B. There was a significant negative correlation between changes in plasma i15-HETE and changes in dynamic compliance between measurement Periods A and B. We conclude that the lung is a source of i15-HETE in ponies with heaves, that these ponies produce greater quantities of i15-HETE than control ponies, and that exposing affected ponies to a barn environment produces acute airway obstruction and increased plasma concentrations of i15-HETE.
Gray
P R
PR
Pulmonary Laboratory, College of Veterinary Medicine, Michigan State University, East Lansing 48824.
Derksen
F J
FJ
Broadstone
R V
RV
Robinson
N E
NE
Johnson
H G
HG
Olson
N C
NC
D000818:Animals; D001249:Asthma / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D004195:Disease Models, Animal; D006734:Horse Diseases / Q000378:metabolism*; D006736:Horses; D006893:Hydroxyeicosatetraenoic Acids / Q000096:biosynthesis* / Q000097:blood; D008168:Lung / Q000378:metabolism*; D008173:Lung Diseases, Obstructive / Q000378:metabolism / Q000662:veterinary*; D011863:Radioimmunoassay; D012129:Respiratory Function Tests / Q000662:veterinary
D006893:Hydroxyeicosatetraenoic Acids; C025984:15-hydroxy-5,8,11,13-eicosatetraenoic acid