AJP - Heart AJP: Cell Physiology
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Am J Physiol Heart Circ Physiol 266: H1339-H1347, 1994;
0363-6135/94 $5.00
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 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 Yang, T.
Right arrow Articles by Levy, M. N.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Yang, T.
Right arrow Articles by Levy, M. N.

AJP - Heart and Circulatory Physiology, Vol 266, Issue 4 1339-H1347, Copyright © 1994 by American Physiological Society

ARTICLES

Antecedent sympathetic stimulation alters time course of chronotropic response to vagal stimulation in dogs

T. Yang, J. B. Senturia and M. N. Levy
Department of Investigative Medicine, Mt. Sinai Medical Center, Case Western Reserve University, Cleveland 44106.

We determined the influence of antecedent sympathetic stimulation on the chronotropic responses of the heart to 10-s strains of vagal stimulation in anesthetized dogs. We used the reciprocal of the slope (m-1) of the initial portion of the vagal response as an index of the time required for the response to reach steady state. In one group of 11 animals, we found that the onset of the response to the vagal stimulation was progressively blunted as we increased the frequency and duration of the antecedent sympathetic stimulation; that is, m-1 increased from 0 to 8.13 +/- 2.75 (SE) and from 0 to 8.22 +/- 2.26, respectively. In three other animals, an antecedent infusion of norepinephrine had a blunting effect that resembled that of antecedent sympathetic stimulation. In 11 other animals, m-1 significantly decreased as we prolonged the elapsed time from the end of sympathetic stimulation to the beginning of vagal stimulation. In six other animals, m-1 was not affected by antecedent atrial pacing at frequencies that were equivalent to those elicited by antecedent sympathetic stimulations. The blunting effect of antecedent sympathetic stimulation was abolished by propranolol administration (1 mg/kg), but it was not affected appreciably by phentolamine administration (2 mg/kg). We conclude that the major blunting effect of antecedent sympathetic stimulation is mediated postjunctionally (i.e., at the level of the automatic cells in the heart.


This article has been cited by other articles:


Home page
 J. Physiol.Home page
J. P. Fisher, A. Kim, C. N. Young, S. Ogoh, P. B. Raven, N. H. Secher, and P. J. Fadel
Influence of ageing on carotid baroreflex peak response latency in humans
J. Physiol., November 15, 2009; 587(22): 5427 - 5439.
[Abstract] [Full Text] [PDF]

Home page
 J. Appl. Physiol.Home page
A. Ostlund and D. Linnarsson
Slowing and attenuation of baroreflex heart rate control with nitrous oxide in exercising men
J Appl Physiol, August 1, 1999; 87(2): 830 - 834.
[Abstract] [Full Text] [PDF]

Home page
 Am. J. Physiol. Regul. Integr. Comp. Physiol.Home page
T. Kawada, M. Sugimachi, T. Shishido, H. Miyano, T. Sato, R. Yoshimura, H. Miyashita, T. Nakahara, J. Alexander Jr., and K. Sunagawa
Simultaneous identification of static and dynamic vagosympathetic interactions in regulating heart rate
Am J Physiol Regulatory Integrative Comp Physiol, March 1, 1999; 276(3): R782 - R789.
[Abstract] [Full Text] [PDF]


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