Journal of Applied Physiology, Vol 40, Issue 6 889-894, Copyright © 1976 by American Physiological Society
Effect of indomethacin and atropine in experimental asthma in conscious guinea pigs
M. C. Michoud, R. S. Fraser, P. D. Pare and J. C. Hogg
Pulmonary mechanics were measured in unanesthetized guinea pigs sensitized
to horseradish peroxidase (HRP) before and during two aerosolized
challenges of this antigen. During the first challenge the pulmonary
resistance increased in all animals. Prior to second challenge the animals
received either atropine (0.2 mg/kg) or indomethacin (10 mg/kg)
intraperitoneally. We found that during the second challenge the
indomethacin group had an increase in pulmonary resistance slightly greater
or similar to that during the first exposure to the antigen, while the
animals treated with atropine had a significantly diminished response (P
less than 0.05). In five guinea pigs sensitized to HRP but challenged with
a nonspecific aerosal made up of rabbit albumin, we found that pulmonary
resistance increased in some animals and that this increase could be
partially blocked by atropine. These results show that indomethacin has no
effect on this model of allergic airways disease. They also confirm the
importance of the vagus nerves in allergic bronchoconstriction and in
addition show that nonspecific hyperirritability can be induced in some
animals by immunization.
