Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology This is an RSS file. You can use it to subscribe to this data in your favourite RSS reader or to display this data on your own website or blog.

Control of testes mass by androgen receptor paralogs in a cichlid
AbstractSteroid hormones play numerous important and diverse roles in the differentiation and development of vertebrate primary and secondary reproductive characteristics. However, the exact role of androgen receptors —which bind circulating androgens—in this regulatory pathway is unclear. Teleost fishes further complicate this question by having two paralogs of the androgen receptor (ARα and ARβ) resulting from a duplication of their ancestral genome. We investigated the functional role of these two ARs on adult testes mass, by eliminating receptor function of one or both paralogs using CRISPR/Cas9 genome editedAsta...
Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology - January 1, 2022 Category: Physiology Source Type: research

The goldfish Carassius auratus: an emerging animal model for comparative cardiac research
AbstractThe use of unconventional model organisms is significantly increasing in different fields of research, widely contributing to advance life sciences understanding. Among fishes, the cyprinidCarassius auratus (goldfish) is largely used for studies on comparative and evolutionary endocrinology, neurobiology, adaptive and conservation physiology, as well as for translational research aimed to explore mechanisms that may be useful in an applicative biomedical context. More recently, the research possibilities offered by the goldfish are further expanded to cardiac studies. A growing literature is available to illustrate...
Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology - January 1, 2022 Category: Physiology Source Type: research

Sulfakinins influence lipid composition and insulin-like peptides level in oenocytes of Zophobas atratus beetles
AbstractInsect sulfakinins are pleiotropic neuropeptides with the homology to vertebrate gastrin/cholecystokinin peptide family. They have been identified in many insect species and affect different metabolic processes. They have a strong influence on feeding and digestion as well as on carbohydrate and lipid processing. Our study reveals that sulfakinins influence fatty acids composition inZophobas atratus oenocytes and regulate insulin-like peptides (ILPs) level in these cells. Oenocytes are cells responsible for maintenance of the body homeostasis and have an important role in the regulation of intermediary metabolism, ...
Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology - January 1, 2022 Category: Physiology Source Type: research

Intracellular taurine deficiency impairs cardiac contractility in rainbow trout (Oncorhynchus mykiss) without affecting aerobic performance
AbstractTaurine is a non-proteinogenic sulfonic acid found in high concentrations inside vertebrate cardiomyocytes and its movement across the sarcolemmal membrane is critical for cell volume regulation. Taurine deficiency is rare in mammals, where it impairs cardiac contractility and leads to congestive heart failure. In fish, cardiac taurine levels vary substantially between species and can decrease by up to 60% in response to environmental change but its contribution to cardiac function is understudied. We addressed this gap in knowledge by generating a taurine-deficient rainbow trout (Oncorhynchus mykiss) model using a...
Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology - January 1, 2022 Category: Physiology Source Type: research

Leaf-cutting ants � critical and voluntary thermal limits show complex responses to size, heating rates, hydration level, and humidity
AbstractThermal variation has complex effects on organisms and they respond to these effects through combined behavioral and physiological mechanisms. However, it is less clear how these traits combine in response to changes in body condition (e.g., size, hydration) and environmental factors that surround the heating process (e.g., relative humidity, start temperatures, heating rates). We tested whether these body conditions and environmental factors influence sequentially measured Voluntary Thermal Maxima (VTmax) and Critical Thermal Maxima, (CTmax) in leaf-cutting ants (Atta sexdens rubropilosa, Forel, 1908). VTmax and C...
Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology - November 27, 2021 Category: Physiology Source Type: research

Leaf-cutting ants ’ critical and voluntary thermal limits show complex responses to size, heating rates, hydration level, and humidity
AbstractThermal variation has complex effects on organisms and they respond to these effects through combined behavioral and physiological mechanisms. However, it is less clear how these traits combine in response to changes in body condition (e.g., size, hydration) and environmental factors that surround the heating process (e.g., relative humidity, start temperatures, heating rates). We tested whether these body conditions and environmental factors influence sequentially measured Voluntary Thermal Maxima (VTmax) and Critical Thermal Maxima, (CTmax) in leaf-cutting ants (Atta sexdens rubropilosa, Forel, 1908). VTmax and C...
Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology - November 27, 2021 Category: Physiology Source Type: research

Seasonal variations in the intermediate metabolism in South American tree-frog Boana pulchella
This study evaluated the main energy substrate levels and metabolism ofB. pulchella in plasma, liver and muscle of male individuals collected in winter, spring, summer and fall in the state of Rio Grande do Sul, Brazil. Our results showed thatB. pulchella has a higher glycolytic oxidation rate in liver (P = 0.0152) and muscle (P = 0.0003) and higher glycogenesis from glucose in muscle (P = 0.0002) in summer, indicating the main energy substrates in this season is glucose. The higher muscle glycogen (P = 0.0008) and lower plasma glucose in fall (P = 0.0134) may indicate an anticipatory regulation for st...
Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology - November 20, 2021 Category: Physiology Source Type: research

Changes in CO2 sensitivity during entrance into, and arousal from hibernation in Ictidomys tridecemlineatus
We examined the time course of the changes in ventilation, O2 consumption rates (\({\dot{\text{V}}}\)o2), CO2 excretion rates, body temperature, and hence the RER and ACR (air convection ratio, ventilation/\({\dot{\text{V}}}\)o2) and the HCVR throughout entrance and arousal into and out of hibernation in 13-lined ground squirrels to confirm this. We observed a significant drop (entrance) and rise (arousal) in the RER produced by hypo- and hyperventilation, respectively. CO2 chemo-sensitivity while the RER was reduced on entrance was blunted and rose late in entrance. On arousal, CO2 chemo-sensitivity was elevated when the ...
Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology - November 5, 2021 Category: Physiology Source Type: research

An expos � of Frappellian Motion
AbstractContrary to the well-recognised role of an abstract in helping to summarise the main points of the following article, this abstract takes its influence from Peter B. Frappell ( �Frapps�) and, therefore, is distracted from its key purpose. While the abstract was supposed to discuss the serious phenomenon of �Frappellian Motion� (FM), someone just passed along some gossip that is heaps more exciting, so �let�s go grab a beer and I�ll talk at you�. (Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology)
Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology - November 1, 2021 Category: Physiology Source Type: research

Extreme hypoxia and high �lactate concentrations in early chicken embryos show that cutaneous oxygen uptake is limited by diffusion and metabolism is partially anaerobic
This study uses fibre-optic sensors to measure oxygen partial pressure (Po2) near, and inside of, the embryo during days 3 �5, and relates the data to total body lactate levels. The study shows that fluids surrounding the embryo greatly impede oxygen diffusion, withPo2 becoming severely hypoxic near the embryo, occasionally almost anoxic inside it. Meanwhile, lactate rises to high levels, and the stored lactate can be later oxidised by the embryo when the chorioallantois takes over and metabolism becomes entirely aerobic. (Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology)
Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology - November 1, 2021 Category: Physiology Source Type: research

Fatty acid profiles of feeding and fasting bears: estimating calibration coefficients, the timeframe of diet estimates, and selective mobilization during hibernation
AbstractAccurate information on diet composition is central to understanding and conserving carnivore populations. Quantitative fatty acid signature analysis (QFASA) has emerged as a powerful tool for estimating the diets of predators, but ambiguities remain about the timeframe of QFASA estimates and the need to account for species-specific patterns of metabolism. We conducted a series of feeding experiments with four juvenile male brown bears (Ursus arctos) to (1) track the timing of changes in adipose tissue composition and QFASA diet estimates in response to a change in diet and (2) quantify the relationship between con...
Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology - October 23, 2021 Category: Physiology Source Type: research

Correction to: Evolution and developmental plasticity of lung structure in high-altitude deer mice
(Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology)
Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology - October 23, 2021 Category: Physiology Source Type: research

City-scale energetics: window on adaptive thermal insulation in North American cities
AbstractPrevious research demonstrated that cities are similar to individual mammals in their relationship between the rate of energy use for heating and outdoor air temperature (Ta). AtTas requiring heating of indoor living spaces, the energy-Ta plot of a city contains information on city-wide thermal insulation (I), making it possible to quantify city-wideI by use of the city as the unit of measure. We develop methods for extracting this insulation information, deriving the methods from prior research on mammals. Using these methods, we address the question: in North America, are cities built in particularly cold locatio...
Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology - October 22, 2021 Category: Physiology Source Type: research

Survivable hypothermia or torpor in a wild-living rat: rare insights broaden our understanding of endothermic physiology
AbstractMaintaining a high and stable body temperature as observed in endothermic mammals and birds is energetically costly. Thus, it is not surprising that we discover more and more heterothermic species that can reduce their energetic needs during energetic bottlenecks through the use of torpor. However, not all heterothermic animals use torpor on a regular basis. Torpor may also be important to an individual ’s probability of survival, and hence fitness, when used infrequently. We here report the observation of a single, ~ 5.5 h long hypothermic bout with a decrease in body temperature by 12 °C in the native Au...
Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology - October 19, 2021 Category: Physiology Source Type: research

Control of testes mass by androgen receptor paralogs in a cichlid
AbstractSteroid hormones play numerous important and diverse roles in the differentiation and development of vertebrate primary and secondary reproductive characteristics. However, the exact role of androgen receptors —which bind circulating androgens—in this regulatory pathway is unclear. Teleost fishes further complicate this question by having two paralogs of the androgen receptor (ARα and ARβ) resulting from a duplication of their ancestral genome. We investigated the functional role of these two ARs on adult testes mass, by eliminating receptor function of one or both paralogs using CRISPR/Cas9 genome editedAsta...
Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology - October 13, 2021 Category: Physiology Source Type: research