Autonomic cardiac regulation facilitates acute heat tolerance in rainbow trout: in situ and in vivo support

被引:23
作者
Gilbert, Matthew J. H. [1 ]
Rani, Varsha [2 ]
McKenzie, Sean M. [1 ]
Farrell, Anthony P. [1 ,2 ]
机构
[1] Univ British Columbia, Dept Zool, 6270 Univ Blvd, Vancouver, BC V6T 1Z4, Canada
[2] Univ British Columbia, Fac Land & Food Syst, 2357 Main Mall, Vancouver, BC V6T 1Z4, Canada
基金
加拿大自然科学与工程研究理事会;
关键词
Upper thermal tolerance; Autonomic regulation; Heart rate; Oncorhynchus mykiss; Cardiac arrhythmia; CORONARY BLOOD-FLOW; SALMON SALMO-SALAR; ONCORHYNCHUS-MYKISS; THERMAL TOLERANCE; ADRENERGIC-STIMULATION; TEMPERATURE-DEPENDENCE; PERFORMANCE; FISH; ACCLIMATION; MYOCARDIUM;
D O I
10.1242/jeb.194365
中图分类号
Q [生物科学];
学科分类号
07 ; 0710 ; 09 ;
摘要
Acute warming in fish increases heart rate (f(H)) and cardiac output to peak values, after which performance plateaus or declines and arrhythmia may occur. This cardiac response can place a convective limitation on systemic oxygen delivery at high temperatures. To test the hypothesis that autonomic cardiac regulation protects cardiac performance in rainbow trout during acute warming, we investigated adrenergic and cholinergic regulation during the onset and progression of cardiac limitations. We explored the direct effects of adrenergic stimulation by acutely warming an in situ working perfused heart until arrhythmia occurred, cooling the heart to restore rhythmicity and rewarming with increasing adrenergic stimulation. Adrenergic stimulation produced a clear, dose-dependent increase in the temperature and peak f(H) achieved prior to the onset of arrhythmia. To examine how this adrenergic protection functions in conjunction with cholinergic vagal inhibition in vivo. rainbow trout fitted with ECG electrodes were acutely warmed in a respirometer until they lost equilibrium (CTmax) with and without muscarinic (atropine) and beta-adrenergic (sotalol) antagonists. Trout exhibited roughly equal and opposing cholinergic and adrenergic tone on f(H) that persisted up to critical temperatures. beta-Adrenergic blockade significantly lowered peak f(H) by 14-17%, while muscarinic blockade significantly lowered the temperature for peak f(H) by 2.0 degrees C. Moreover, muscarinic and beta-adrenergic blockers injected individually or together significantly reduced CTmax by up to 3 degrees C, indicating for the first time that cardiac adrenergic stimulation and cholinergic inhibition can enhance acute heat tolerance in rainbow trout at the level of the heart and the whole animal.
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页数:10
相关论文
共 72 条
[1]   Cold acclimation increases basal heart rate but decreases its thermal tolerance in rainbow trout (Oncorhynchus mykiss) [J].
Aho, E ;
Vornanen, M .
JOURNAL OF COMPARATIVE PHYSIOLOGY B-BIOCHEMICAL SYSTEMIC AND ENVIRONMENTAL PHYSIOLOGY, 2001, 171 (02) :173-179
[2]   Ionic channels underlying the ventricular action potential in zebrafish embryo [J].
Alday, Aintzane ;
Alonso, Hiart ;
Gallego, Monica ;
Urrutia, Janire ;
Letamendia, Ainhoa ;
Callol, Caries ;
Casis, Oscar .
PHARMACOLOGICAL RESEARCH, 2014, 84 :26-31
[3]   Cholinergic and adrenergic tones in the control of heart rate in teleosts. How should they be calculated? [J].
Altimiras, J ;
Aissaoui, A ;
Tort, L ;
Axelsson, M .
COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY A-MOLECULAR & INTEGRATIVE PHYSIOLOGY, 1997, 118 (01) :131-139
[4]  
[Anonymous], 2014, The R Foundation for Statistical Computing
[5]  
[Anonymous], INT C MICROWAVE MILL, DOI DOI 10.1371/J0URNAL.P0NE
[6]  
[Anonymous], 1947, EFFECTS ENV ANIMAL A
[7]   Atlantic salmon show capability for cardiac acclimation to warm temperatures [J].
Anttila, Katja ;
Couturier, Christine S. ;
Overli, Oyvind ;
Johnsen, Arild ;
Marthinsen, Gunnhild ;
Nilsson, Goran E. ;
Farrell, Anthony P. .
NATURE COMMUNICATIONS, 2014, 5
[8]  
ASK JA, 1981, J COMP PHYSIOL, V143, P161
[9]   CORONARY BLOOD-FLOW INVIVO IN THE COHO SALMON (ONCORHYNCHUS-KISUTCH) [J].
AXELSSON, M ;
FARRELL, AP .
AMERICAN JOURNAL OF PHYSIOLOGY, 1993, 264 (05) :R963-R971
[10]   Effects of seasonal acclimatization on temperature dependence of cardiac excitability in the roach, Rutilus rutilus [J].
Badr, A. ;
El-Sayed, M. F. ;
Vornanen, M. .
JOURNAL OF EXPERIMENTAL BIOLOGY, 2016, 219 (10) :1495-1504