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 Courtice, G.
Right arrow Search for Related Content
PubMed
Right arrow Articles by Courtice, G.

Journal of Experimental Biology, Vol 149, Issue 1 439-447, Copyright © 1990 by Company of Biologists

JOURNAL ARTICLES

Effect of temperature on cardiac vagal action in the toad Bufo marinus

GP Courtice
School of Physiology and Pharmacology, University of New South Wales, Kensington, Sydney, Australia.

The effect of temperature on the action of the vagus nerve on the heart was studied in the toad Bufo marinus. Experiments were performed on two groups of toads, in one the heart was perfused at a constant rate with oxygenated Ringer's solution and in the other the circulation was left intact. In all toads there was a linear relationship between pulse interval (PI) and the frequency of vagal stimulation (fv) at any one temperature. The slope of this relationship changed with temperature, the effectiveness of the vagus (delta PI/delta fv) increasing with decreasing temperature. At low temperatures the vagus nerves of intact toads were more effective than in those with perfused hearts. It is suggested that, in intact toads at low temperatures, cardiac output decreases and the consequent accumulation of acetylcholine leads to increased vagal effectiveness.


This article has been cited by other articles:


Home page
 J. Exp. Biol.Home page
I.-K. S. Aggeli, C. Gaitanaki, A. Lazou, and I. Beis
Hyperosmotic and thermal stresses activate p38-MAPK in the perfused amphibian heart
J. Exp. Biol., February 15, 2002; 205(4): 443 - 454.
[Abstract] [Full Text] [PDF]

Home page
 J. Exp. Biol.Home page
A. Gamperl, W. Milsom, A. Farrell, and T Wang
Cardiorespiratory responses of the toad (Bufo marinus) to hypoxia at two different temperatures
J. Exp. Biol., January 12, 1999; 202(24): 3647 - 3658.
[Abstract] [PDF]


© The Company of Biologists Ltd 1990