QUICK SEARCH:   [advanced] Author: Keyword(s):
Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents

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

Journal of Experimental Biology 37,719-731 (1960)
Published by Company of Biologists 1960

The Reflex Co-ordination of the Heart Beat with Respiration in the Dogfish

G. H. SATCHELL ¹

¹ Department of Physiology, Otago Medical School, New Zealand

1. The hearts of Squalus lebruni and Mustelus antarcticus beat at intervals that approximate to some simple multiple (1-4) of respiratory cycle length.

2. The beat tends to be initiated during a particular phase of the respiratory cycle, most commonly just before or just after the opening of the mouth.

3. Possible mechanisms of this co-ordination are considered and evidence is presented to show that it is reflexly mediated. Fibres from receptors fired by pharyngeal dilatation are believed to constitute the afferent limb, and the cardiac vagi the efferent limb of the reflex arc.

4. Simultaneous records of blood pressure have been made from the 1st afferent branchial artery and the coeliac artery. By subtraction, the differential pressure across the gill vessels has been calculated and found to have a peak early in the cardiac cycle.

5. Simultaneous photo-electric records of gill opacity and branchial blood pressure show the gill vessels to be compliant. It is concluded that there is a brief period of rapid blood flow early in each cardiac cycle.

6. Calculations from simultaneous records of the electrocardiogram and branchial blood pressure showed that heart beats originating near the time of mouth opening caused a rapid flow of blood through the gills at the time that water was expelled across them.

7. It is suggested that this synchronization of the periods of rapid flow of blood and water serves to maintain the diffusion gradient of oxygen across the gill epithelium.

This article has been cited by other articles:

				A. P. Farrell Tribute to P. L. Lutz: a message from the heart - why hypoxic bradycardia in fishes? J. Exp. Biol., May 15, 2007; 210(10): 1715 - 1725. [Abstract] [Full Text] [PDF]

				F. Yasuma and J.-i. Hayano Respiratory Sinus Arrhythmia: Why Does the Heartbeat Synchronize With Respiratory Rhythm? Chest, February 1, 2004; 125(2): 683 - 690. [Abstract] [Full Text] [PDF]

				J. Hayano and F. Yasuma Hypothesis: respiratory sinus arrhythmia is an intrinsic resting function of cardiopulmonary system Cardiovasc Res, April 1, 2003; 58(1): 1 - 9. [Abstract] [Full Text] [PDF]

				E. W. Taylor, D. Jordan, and J. H. Coote Central Control of the Cardiovascular and Respiratory Systems and Their Interactions in Vertebrates Physiol Rev, July 1, 1999; 79(3): 855 - 916. [Abstract] [Full Text] [PDF]

				P. W. Gilbert and S. D. Douglas Electrocardiographic Studies of Free-Swimming Sharks Science, June 28, 1963; 140(3574): 1396 - 1396. [Abstract] [PDF]