| Effect of coronary perfusion on the basal performance, volume loading and oxygen consumption in the isolated resistance-headed heart of the trout Oncorhynchus mykiss. | |
| | |
MedLine Citation:
|
PMID: 14555740 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
|
Basal performance, volume loading response and oxygen consumption were determined in a resistance-headed preparation of the isolated trout heart. Two groups of hearts were used: the +CF group, in which the coronary vascular tree was perfused with a flow directly related to the pressure generated by the heart, and the -CF group, in which the coronary flow was set to zero. As a criterion for setting basal performance, the atrial input pressure was set in order to induce the ventricle to produce a cardiac output of 15 ml min(-1) kg(-1). Once basal conditions were obtained, the preparation was perfused for 30 min, and atrial and aortic pressure, cardiac output, heart rate, coronary pressure and coronary flow were determined at 5 min intervals. At the onset of perfusion, there was no difference in the basal performance between the two groups: the same preload was necessary to get the same cardiac output in both perfusion groups. None of the other performance parameters determined were different. However, after only 5 min of perfusion, the -CF hearts displayed significant adjustments, with increased atrial preload and ventricular preload (mean atrial pressure), and a significant decrease in cardiac output. At the end of the 30 min basal perfusion period, hearts were challenged with a stepwise increase in preload in order to obtain maximal stroke work (volume loading). The effect of coronary perfusion on the heart's response to volume loading was highly significant: the stroke work-preload relationship was significantly shifted towards higher preload values in the -CF group. Also, the maximal work produced by the heart under the experimental conditions used was lower in the -CF group. Rate of oxygen consumption of the heart increased significantly with volume loading, from a basal value of approximately 20 microl O2 min(-1) g(-1) to approx. 40 microl O2 min(-1) g(-1), but was not significantly affected by the absence of coronary perfusion. Mechanical efficiency under basal conditions was approximately 17%, but was not affected by either volume loading or coronary perfusion. Taken as a whole, these data represent direct evidence of the effect of coronary perfusion on the mechanical performance of the trout heart, but also show that these effects are limited by significant self-adjustments that occur in the heart. |
| | |
Authors:
|
C Agnisola; L Petersen; T Mustafa |
Publication Detail:
|
Type: Comparative Study; Journal Article; Research Support, Non-U.S. Gov't |
Journal Detail:
|
Title: The Journal of experimental biology Volume: 206 ISSN: 0022-0949 ISO Abbreviation: J. Exp. Biol. Publication Date: 2003 Nov |
Date Detail:
|
Created Date: 2003-10-13 Completed Date: 2004-07-14 Revised Date: 2006-11-15 |
Medline Journal Info:
|
Nlm Unique ID: 0243705 Medline TA: J Exp Biol Country: England |
Other Details:
|
Languages: eng Pagination: 4003-10 Citation Subset: IM |
Affiliation:
|
Università degli studi di Napoli, Dipartimento di Fisiologia Generale ed Ambientale, via Mezzocannone 8, 80134-Napoli, Italy. agnisola@unina.it |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
Analysis of Variance Animals Blood Pressure / physiology Blood Volume / physiology* Cardiac Output / physiology Coronary Circulation / physiology Heart / physiology* Oncorhynchus mykiss / physiology* Oxygen Consumption / physiology* Perfusion / methods* Time Factors |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: Mechanosensory-induced behavioural gregarization in the desert locust Schistocerca gregaria.
Next Document: Electrical activity of caudal neurosecretory neurons in seawater- and freshwater-adapted flounder: r...