spacer gif spacer gif spacer gif spacer gif spacer gif
QUICK SEARCH:   [advanced]


spacer gif
     Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents    

This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Benchetrit, G
Right arrow Articles by Dejours, P
Right arrow Search for Related Content
PubMed
Right arrow Articles by Benchetrit, G
Right arrow Articles by Dejours, P

Journal of Experimental Biology, Vol 87, Issue 1 229-236, Copyright © 1980 by Company of Biologists

JOURNAL ARTICLES

Ventilatory CO2 drive in the tortoise Testudo horsfieldi

G Benchetrit and P Dejours

1. Ventilation was recorded by pneumotachography, before and after bilateral vagotomy, in conscious tortoises (Testudo horsfieldi) (breathing 0, 2, 3 or 4% CO2 in air or oxygen). 2. Each breath consists of expiratory and inspiratory phases and an apneic plateau (absence of air flow). Inhalation of hypercapnic mixtures led to increased ventilatory flow, augmentation of tidal volume, and an increase in respiratory frequency through the shortening of the apneic plateau. 3. Intact tortoises breathing hypercapnic-hyperoxic mixtures hyperventilated less than with hypercapnic-normoxic mixtures. 4. In bivagotomized animals, the respiratory frequency decreased, the expiratory and inspiratory durations lengthened, and the apneic plateau was prolonged. The tidal volume was increased, but ventilation, nevertheless, decreased slightly. 5. Bivagotomized animals breathing hypercapnic-normoxic or hypercapnic-hyperoxic mixtures hyperventilated, but less than intact animals under the same conditions. 6. It is concluded that in tortoises there are: (1) peripheral chemoreceptors which are innervated by branches of the vagus nerves, and are sensitive to CO2; and (2) an extrathoracic, probably central, ventilatory CO2 drive.


This article has been cited by other articles:


Home page
 Am. J. Physiol. Regul. Integr. Comp. Physiol.Home page
S. M. Johnson and R. J. Creighton
Spinal cord injury-induced changes in breathing are not due to supraspinal plasticity in turtles (Pseudemys scripta)
Am J Physiol Regulatory Integrative Comp Physiol, December 1, 2005; 289(6): R1550 - R1561.
[Abstract] [Full Text] [PDF]

Home page
 J. Neurophysiol.Home page
T. Inoue, Z. Haque, K. Lukowiak, and N. I. Syed
Hypoxia-Induced Respiratory Patterned Activity in Lymnaea Originates at the Periphery
J Neurophysiol, July 1, 2001; 86(1): 156 - 163.
[Abstract] [Full Text] [PDF]

Home page
 J. Exp. Biol.Home page
J. Herman and N. Smatresk
Cardiorespiratory response to progressive hypoxia and hypercapnia in the turtle trachemys scripta
J. Exp. Biol., January 11, 1999; 202(22): 3205 - 3213.
[Abstract] [PDF]

Home page
 J. Appl. Physiol.Home page
S. M. Johnson, R. A. Johnson, and G. S. Mitchell
Hypoxia, temperature, and pH/CO2 effects on respiratory discharge from a turtle brain stem preparation
J Appl Physiol, February 1, 1998; 84(2): 649 - 660.
[Abstract] [Full Text] [PDF]


© The Company of Biologists Ltd 1980