Journal of Applied Physiology Ad Instruments
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

J Appl Physiol 77: 742-750, 1994;
8750-7587/94 $5.00
This Article
Right arrow Full Text (PDF)
Right arrow Submit a response
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Hedrick, M. S.
Right arrow Articles by Bisgard, G. E.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Hedrick, M. S.
Right arrow Articles by Bisgard, G. E.

Journal of Applied Physiology, Vol 77, Issue 2 742-750, Copyright © 1994 by American Physiological Society

ARTICLES

Modulation of respiratory rhythm by alpha 2-adrenoceptors in awake and anesthetized goats

M. S. Hedrick, M. L. Ryan, J. Pizarro and G. E. Bisgard
Department of Comparative Biosciences, University of Wisconsin, Madison 53706.

The purpose of this study was to examine the effects of alpha 2-adrenoceptor agonists in the control of breathing with goats that were either awake (n = 7) or anesthetized and artificially ventilated (n = 11). Awake goats infused intravenously with either of the alpha 2-agonists clonidine (1.0-6.0 micrograms/kg) or guanabenz (15.0-63.0 micrograms/kg) exhibited two distinct ventilatory patterns. One pattern was characterized by tachypnea in which respiratory frequency and minute ventilation increased to approximately 50% above control values. A second ventilatory pattern consisted of slow breathing with reductions of respiratory frequency and minute ventilation and highly variable expiratory duration intervals. These two patterns were unaffected by bilateral carotid body denervation. In anesthetized goats, alpha 2-agonists also caused an arrhythmia in phrenic nerve activity that was similar to the slow breathing pattern seen in awake goats. Respiratory disturbances were abolished by the selective alpha 2-receptor antagonist SKF-86466 (100-500 micrograms/kg), indicating that the effects are mediated by alpha 2-receptors. The results suggest that stimulation of alpha 2-adrenoceptors generally has an inhibitory effect on breathing in goats. The disruption of ventilation with clonidine or guanabenz suggests that alpha 2-adrenoceptors may play an important role in the control of central respiratory rhythm.


This article has been cited by other articles:


Home page
 J. Appl. Physiol.Home page
K. D. O'Halloran and G. E. Bisgard
Upper airway pressure-flow relationships and pharyngeal constrictor EMG activity during prolonged expiration in awake goats
J Appl Physiol, July 1, 2008; 105(1): 100 - 108.
[Abstract] [Full Text] [PDF]

Home page
 Exp PhysiolHome page
K. Kaczynska and M. Szereda-Przestaszewska
Clonidine-evoked respiratory effects in anaesthetized rats
Exp Physiol, January 1, 2006; 91(1): 269 - 275.
[Abstract] [Full Text] [PDF]

Home page
 J. Appl. Physiol.Home page
F. P. Tolentino-Silva, M. A. Haxhiu, P. Ernsberger, S. Waldbaum, and I. A. Dreshaj
Differential cardiorespiratory control elicited by activation of ventral medullary sites in mice
J Appl Physiol, August 1, 2000; 89(2): 437 - 444.
[Abstract] [Full Text] [PDF]

Home page
 J. Appl. Physiol.Home page
K. D. O'Halloran, J. K. Herman, and G. E. Bisgard
Differential effects of clonidine on upper airway abductor and adductor muscle activity in awake goats
J Appl Physiol, August 1, 1999; 87(2): 590 - 597.
[Abstract] [Full Text] [PDF]

Home page
 J. Appl. Physiol.Home page
M. S. Hedrick, M. R. Dwinell, P. L. Janssen, J. Pizarro, and G. E. Bisgard
Differential respiratory muscle recruitment induced by clonidine in awake goats
J Appl Physiol, April 1, 1998; 84(4): 1198 - 1207.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Visit Other APS Journals Online