Thermal acclimation and seasonal acclimatization: a comparative study of cardiac response to prolonged temperature change in shorthorn sculpin

Cardiovascular adaptations that permit successful exploitation of polar marine waters by fish requires a capacity to negate or compensate for the depressive effects of low temperatures on physiological processes. Here, we examined the effects of acute and chronic temperature change on the maximum cardiac performance of shorthorn sculpin (Myoxocephalus scorpius (L., 1758)) captured above the Arctic Circle. Our aim was to establish if the sculpin’s success at low temperatures was achieved through thermal independence of cardiac function or via thermal compensation as a result of acclimation. Maximum cardiac performance was assessed at both 1 and 6 °C with a working perfused heart preparation that was obtained after fish had been acclimated to either 1 or 6 °C. Thus, tests were performed at the fish’s acclimation temperature and with an acute temperature change. Maximum cardiac output, which was relatively large (>50 mL·min−1·kg−1 body mass) for a benthic fish at a frigid temperature, was found to be independent of both acclimation temperature and test temperature. While maximum β-adrenergic stimulation produced positive chronotropy at both acclimation temperatures, inotropic effects were weak or absent. We conclude that thermal independence of cardiac performance at low temperature likely facilitated the exploitation of polar waters by the shorthorn sculpin.

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Influences of thermal acclimation and acute temperature change on the motility of epithelial wound-healing cells (keratocytes) of tropical, temperate and Antarctic fish

Journal of Experimental Biology ◽

10.1242/jeb.00706 ◽

2003 ◽

Vol 206 (24) ◽

pp. 4539-4551 ◽

Cited By ~ 32

Author(s):

R. A. Ream

Keyword(s):

Wound Healing ◽

Temperature Change ◽

Antarctic Fish ◽

Thermal Acclimation ◽

Epithelial Wound Healing

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Rhodamine 123 permeability through the catfish intestinal wall: Relationship to thermal acclimation and acute temperature change

Comparative Biochemistry and Physiology Part C Toxicology & Pharmacology ◽

10.1016/j.cbpc.2006.08.007 ◽

2006 ◽

Vol 144 (3) ◽

pp. 205-215 ◽

Cited By ~ 5

Author(s):

Kevin M. Kleinow ◽

Brad D. Johnston ◽

Earnestine P. Holmes ◽

Matthew E. McCarrol

Keyword(s):

Temperature Change ◽

Intestinal Wall ◽

Thermal Acclimation ◽

Rhodamine 123

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A Comparative Study of the Cardiac Response to Bhastrika: A Yogic Breathing Exercise and the Exercise Tolerance Test

International Journal of Yoga Therapy ◽

10.17761/ijyt.7.1.y354313llp003015 ◽

1997 ◽

Vol 7 (1) ◽

pp. 35-42

Author(s):

Kevin Hoffman ◽

John Clarke

Keyword(s):

Comparative Study ◽

Exercise Tolerance ◽

Tolerance Test ◽

Cardiac Response ◽

Diaphragmatic Breathing ◽

Breathing Exercise ◽

Breathing Exercises ◽

Exercise Tolerance Test ◽

Yogic Breathing

Yogic breathing exercises form a spectrum from simple, diaphragmatic breathing to complex exercises involving breath retention and visualization. Many of the advanced exercises are potentially harmful if not taught and practiced systematically.

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