|
|
||||||||
Long, W. Q., G. G. Giesbrecht, and N. R. Anthonisen. Ventilatory response to moderate hypoxia in awake
chemodenervated cats. J. Appl. Physiol. 74(2): 805-810, 1993.
In humans and cats the ventilatory response to 30 min of
moderate hypoxia (arterial PO2 40-55
Torr) is biphasic: ventilation increases sharply for the first 5 min
and then declines. In humans there is evidence that the decline is
dependent on the initial increase. We therefore examined ventilatory
responses to moderate isocapnic hypoxia in awake cats with and without
carotid body denervation. Cats underwent denervation or a sham
operation. Then they were studied in a Drorbaugh-Fenn plethysmograph
while ventilation, arterial PO2, and end-tidal PO2 and PCO2 were
measured. Three sham-operated and four denervated cats were studied
with room air as the control. Sham animals demonstrated a biphasic
response: ventilation rose to 211% of control at 5 min and fell to
114% of control at 25 min. Denervated animals showed neither the
initial increase nor the subsequent decrease in ventilation. Three
sham-operated and three denervated cats were studied with 2%
CO2 added to the inspirate. Results were similar: intact
cats showed a biphasic response to hypoxia, whereas denervated cats
showed neither an increase nor a decrease in ventilation. Preliminary
experiments showed that hypoxia was not associated with changes in
CO2 output or systemic blood pressure in either denervated
or intact animals. We conclude that depression of ventilation does not
occur in awake denervated cats in response to moderate hypoxia
and that the decline in ventilation that occurs in intact cats is in
some way dependent on peripheral chemoreceptor output.
This article has been cited by other articles:
![]() |
K. J. Cummings and R. J. A. Wilson Time-dependent modulation of carotid body afferent activity during and after intermittent hypoxia Am J Physiol Regulatory Integrative Comp Physiol, June 1, 2005; 288(6): R1571 - R1580. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. J. Pandit, D. Sjogren, S. G. E. Lindahl, and A. Sollevi Hypoxic ventilatory response: the effects of CO2 and of sustained hypoxia. Anesth. Analg., March 1, 1999; 88(3): 695 - 696. [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |