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 GRAHAM, M.
Right arrow Articles by FARRELL, A.
Right arrow Search for Related Content
PubMed
Right arrow Articles by GRAHAM, M.
Right arrow Articles by FARRELL, A.
Journal of Experimental Biology 118,173-183 (1985)
Published by Company of Biologists 1985


The Seasonal Intrinsic Cardiac Performance of a Marine Teleost

MARK GRAHAM 1 and ANTHONY FARRELL 2

1 Marine Sciences Research Laboratory, Memorial University of Newfoundland, St. John's Newfoundland A1C 5S7; Department of Biological Sciences, Simon Fraser University, Burnaby, British Columbia V5A 1S7
2 Department of Biological Sciences, Simon Fraser University, Burnaby, British Columbia V5A 1S7

1. An in situ heart preparation was used to evaluate cardiac performance in the sea raven, Hemitripterus americanus, under physiological inflow and outflow pressure conditions. Winter and summer fish were subjected to an acute 10°C temperature change from the seasonal ambient value. The maximum cardiac output (V·b) under each temperature condition was determined by altering inflow pressure to the heart.

2. Acute temperature increase produced positive chronotropic and inotropic effects in winter fish. Acute temperature decrease produced a negative chronotropic and inotropic effect in summer fish.

3. The inotropic and chronotropic states of the heart were different in winter and summer fish. Intrinsic heart rate was higher in summer fish at all experimental temperatures. The sensitivity of the summer fish hearts to input pressure was also greater, especially during the warm experimental temperatures.

4. It was evident from heartbeat rate measurements and power output calculations that the advent of summer and winter seasons did not promote any compensatory ability in intrinsic heart function.

Key words: Fish, heart, seasonal

Accepted on March 4, 1985




This article has been cited by other articles:


Home page
Am. J. Physiol. Regul. Integr. Comp. Physiol.Home page
E. Sandblom and M. Axelsson
Venous hemodynamic responses to acute temperature increase in the rainbow trout (Oncorhynchus mykiss)
Am J Physiol Regulatory Integrative Comp Physiol, June 1, 2007; 292(6): R2292 - R2298.
[Abstract] [Full Text] [PDF]




© The Company of Biologists Ltd 1985