» Articles » PMID: 35243360

Effect of Thermal Variation on the Cardiac Thermal Limits of a Eurythermal Marine Teleost ()

Overview
Date 2022 Mar 4
PMID 35243360
Authors
Affiliations
Soon will be listed here.
Abstract

Although most animals live in complex, thermally variable environments, the impact of this variability on specific physiological systems is still unresolved. The ectotherm heart is known to change in both structure and function to ensure appropriate oxygen delivery under different thermal regimes, but the plasticity of the upper thermal limits of the heart under stable or variable thermal acclimation conditions remains unknown. To investigate the role of thermal variability on cardiac acclimation potential, we acclimated a eurythermal fish, opaleye (), to three static temperature treatments (13, 16, and 19 °C) as well as two oscillating treatments which cycled between maximum and minimum temperatures every 12 h (13-19 °C and 16-22 °C). These temperatures and daily thermal ranges were chosen to mimic the conditions observed in the rocky intertidal environments in Santa Barbara, CA, USA where the fish were collected. We hypothesized that increasing temperature would increase upper thermal limits of the heart, and that variable acclimations would result in broader acute thermal performance curves (TPCs) compared to static acclimations. We measured maximum heart rate during acute warming to determine cardiac thermal performance (i.e., the temperature corresponding to the onset of cardiac arrythmia, the temperature at maximum heart rate, absolute maximum heart rate, and the Arrhenius breakpoint temperature) and construct acute TPCs. Rising static acclimation temperatures increased upper thermal limits but had no impact on peak maximum heart rate. The warmest static temperature did, however, cause a narrowing of the acute TPC. Fish acclimated to variable conditions had the same upper thermal limits compared to fish acclimated to static conditions with the same mean temperature in all metrics of thermal performance. Further, there was no significant broadening of the acute TPC. This study suggests that cardiac plasticity is robust to thermal variation in this eurythermal fish.

Citing Articles

Despite plasticity, heatwaves are costly for a coral reef fish.

Van Wert J, Birnie-Gauvin K, Gallagher J, Hardison E, Landfield K, Burkepile D Sci Rep. 2024; 14(1):13320.

PMID: 38858427 PMC: 11164959. DOI: 10.1038/s41598-024-63273-8.


Body size and temperature affect metabolic and cardiac thermal tolerance in fish.

Kraskura K, Hardison E, Eliason E Sci Rep. 2023; 13(1):17900.

PMID: 37857749 PMC: 10587238. DOI: 10.1038/s41598-023-44574-w.


Diet changes thermal acclimation capacity, but not acclimation rate, in a marine ectotherm () during warming.

Hardison E, Schwieterman G, Eliason E Proc Biol Sci. 2023; 290(1995):20222505.

PMID: 36987639 PMC: 10050929. DOI: 10.1098/rspb.2022.2505.

References
1.
Alderman S, Klaiman J, Deck C, Gillis T . Effect of cold acclimation on troponin I isoform expression in striated muscle of rainbow trout. Am J Physiol Regul Integr Comp Physiol. 2012; 303(2):R168-76. DOI: 10.1152/ajpregu.00127.2012. View

2.
Keen A, Klaiman J, Shiels H, Gillis T . Temperature-induced cardiac remodelling in fish. J Exp Biol. 2016; 220(Pt 2):147-160. PMC: 5278617. DOI: 10.1242/jeb.128496. View

3.
Lefevre S, Wang T, McKenzie D . The role of mechanistic physiology in investigating impacts of global warming on fishes. J Exp Biol. 2021; 224(Pt Suppl 1). DOI: 10.1242/jeb.238840. View

4.
Genge C, Stevens C, Davidson W, Singh G, Tieleman D, Tibbits G . Functional Divergence in Teleost Cardiac Troponin Paralogs Guides Variation in the Interaction of TnI Switch Region with TnC. Genome Biol Evol. 2016; 8(4):994-1011. PMC: 4860682. DOI: 10.1093/gbe/evw044. View

5.
Cooper C, Kristan 3rd W, Eme J . Thermal tolerance and routine oxygen consumption of convict cichlid, Archocentrus nigrofasciatus, acclimated to constant temperatures (20 °C and 30 °C) and a daily temperature cycle (20 °C → 30 °C). J Comp Physiol B. 2021; 191(3):479-491. DOI: 10.1007/s00360-021-01341-5. View