...., and then warmed to their critical thermal maximum (CT max ) at 2°C h −1 . Fish exposed to 50% air sat. became bradycardic, were unable to increase heart rate ( f H ) when warmed, and had lower values for metabolic scope and CT max (21.3 vs 26.1°C in normoxic fish). The effects of 75% air sat. on cardiorespiratory...

...William Joyce; Holly A. Shiels; Craig E. Franklin ABSTRACT Cardiac phenotypic plasticity, the remodelling of heart structure and function, is a response to any sustained (or repeated) stimulus or stressor that results in a change in heart performance. Cardiac plasticity can be either adaptive...

...Miguel A. López-Unzu; María Teresa Soto-Navarrete; Valentín Sans-Coma; Borja Fernández; Ana Carmen Durán ABSTRACT The ventricle of the vertebrate heart is the main segment of the cardiac outflow region. Compared with other cardiac components, it shows remarkable histomorphological variation among...

... (e.g. lipids, amino acids, vitamins, minerals) impact the heart's structure and performance, and thus whole-animal resilience to environmental change. Notably, many animals can alter their diet in response to environmental cues, depending on the context. Yet, most studies feed animals ad libitum using...

...Andreas Fahlman; Warren Burggren; William K. Milsom ABSTRACT The dive response involves three main components – breath holding, reduced heart rate and increased peripheral vasoconstriction – and is ubiquitous during forced dives in air-breathing vertebrates; however, numerous studies in free-diving...

... activity was reduced in the heart after 1 week of anoxia in crucian carp, together with a downregulation of ATP synthase subunit gene expression. However, the morphology of cardiac mitochondria was not affected by 1 week of anoxia, even with a large increase in mitofusin 2 mRNA expression. Cardiac citrate...

... temperature-dependent effects. First, while differences in resting heart rate ( f H ) between groups were predictable based on previous research (range ∼28–65 beats min −1 ), with values for 1°C-acclimated fish slightly higher than those of acutely exposed conspecifics, the resting cardiac output ( ) of 1°C...

... to the heart's function when environmental conditions are variable. Consequently, exploring factors that trigger cardiac remodelling with acclimation to new environments represents a marvellous opportunity for performing mechanistic studies that minimize the genetic differences that accompany cross-species...

... damage to their hearts. In contrast, for mammals, the ischemia–reperfusion (IR) injury that leads to tissue damage during a heart attack is initiated by a burst of superoxide (O 2 · − ) production from the mitochondrial respiratory chain upon reperfusion of ischemic tissue. Whether turtles avoid...

...Georg Welzel; Stefan Schuster ABSTRACT High voltage electric shocks cause life threatening cardiac injuries such as sudden cardiac standstill or severe myocardial injury. Here, we analysed the physiology of the heart of the strongly electric catfish ( Malapterurus beninensis ) that stuns prey...

... accounting for body mass, heart ventricle mass was not related to variation in MMR or SMR, indicating that the quality of the heart (i.e. the capacity for mitochondrial metabolism) was more influential than heart size. Finally, the myocardial oxygen consumption required to offset the dissipation...

... Summary: The circulation of hemolymph in the antenna of Drosophila is powered by the rhythmic contraction of an auto-active somatic muscle which runs through the brain. Circulatory system Pulsatile organs Heart Pulsatility National Institutes of Health http://dx.doi.org/10.13039...

..., superoxide dismutase (SOD) activity and NAD + levels, and it prevented HFD-induced or cardiac Nmnat knockdown-induced cardiac lipid accumulation, malondialdehyde (MDA) content and fibrillation increase, and fractional shortening decrease. Cardiac Nmnat overexpression also activated heart Nmnat/NAD + /SIR2...

...Denis V. Abramochkin; Vladislav S. Kuzmin; Vladimir Matchkov; Andrey A. Kamensky; Tobias Wang ABSTRACT To provide the first description of the exact location of primary pacemaker of the squamate heart, we used sharp microelectrode impalements and optical mapping of isolated sinus venosus...

... of high temperatures than Arctic char, and why char are particularly vulnerable to climate change. Thermal tolerance Heart Myocardium Red muscle Acute Temperature acclimation Muscle performance Muscle efficiency Natural Sciences and Engineering Research Council of Canada http...

... enhanced anoxia survival in adult but not hatchling turtles. To test this, adult and hatchling turtles were acclimated to either 20°C (warm) or 3°C (cold) for 5 weeks, and then the heart ventricles were collected for quantitative proteomic analysis. The relative abundance of 1316 identified proteins...

... and complex I activity. * Author for correspondence ( [email protected] ) Competing interests The authors declare no competing or financial interests. 3 2 2021 18 3 2021 © 2021. Published by The Company of Biologists Ltd 2021 Summary: Decreases in trout heart...

... (5H fish), on in vivo and spontaneous heart rate ( f H ), electrocardiogram, ventricular action potential (AP) shape and duration (APD), the background inward rectifier ( I K1 ) and rapid delayed rectifier ( I Kr ) K + currents and ventricular gene expression of proteins involved in excitation...

... and development. Turtle Crocodile Chicken Embryo Heart The vertebrate heart shows great variability in the number of chambers according to animal physiology, life history and phylogeny. Generally in reptiles, ventricular septation varies among clades from a partially septated ventricle in some...

...Tatiana S. Filatova; Denis V. Abramochkin; Holly A. Shiels ABSTRACT Birds occupy a unique position in the evolution of cardiac design. Their hearts are capable of cardiac performance on par with, or exceeding that of mammals, and yet the structure of their cardiomyocytes resembles those of reptiles...