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Effects of Hyperoxia and Allergic Airway
Inflammation on Cough Reflex Intensity in Guinea Pigs
M. BROZMANOVÁ, J. HANÁČEK,
M. TATÁR, A. STRAPKOVÁ1, P.
SZÉPE2
Department of Pathophysiology, 1Department
of Pharmacology and 2Department of Pathology,
Jessenius Faculty of Medicine, Comenius University, Martin,
Slovak Republic
Received
July 9, 2001
Accepted February 11, 2002
Summary
Toxic influence of high oxygen concentration on pulmonary
function and structures has been known for many years. However,
the influence of high oxygen concentration breathing on
defensive respiratory reflexes is still not clear. In our
previous experiments, we found an inhibitory effect of 100 %
oxygen breathing on cough reflex intensity in healthy guinea
pigs. The present study was designed to detect the effects of
hyperoxia on cough reflex in guinea pigs with allergic airway
inflammation. In the first phase of our experiment, the animals
were sensitized with ovalbumin. Thirty-two sensitized animals
were used in two separate experiments according to oxygen
concentration breathing: 100 % or 50 % oxygen for 60 h
continuously. In each experiment, one group of animals was
exposed to hyperoxia, another to ambient air. The cough reflex
was induced both by aerosol of citric acid before sensitization,
then in sensitized animals at 24 h and 60 h of exposition to
oxygen/air in awake animals, and by mechanical stimulation of
airway mucosa in anesthetized animals just after the end of the
experiment. In contrast to 50 % oxygen, 100 % oxygen breathing
leads to significant decrease in chemically induced cough in
guinea pigs with allergic inflammation. No significant changes
were present in cough induced by mechanical stimulation of
airways.
Key
words
Hyperoxia · Allergic inflammation · Ovalbumin · Citric acid
cough · Mechanically induced cough
Reprint
requests
RNDr. Mariana Brozmanová, Department of Pathophysiology,
Jessenius Faculty of Medicine, Comenius University, Sklabinská
26, 037 53 Martin, Slovak Republic, e-mail:
brozmanova@jfmed.uniba.sk
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