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.

The microtubule signature in cardiac disease: etiology, disease stage, and age dependency
AbstractEmploying animal models to study heart failure (HF) has become indispensable to discover and test novel therapies, but their translatability remains challenging. Although cytoskeletal alterations are linked to HF, the tubulin signature of common experimental models has been incompletely defined. Here, we assessed the tubulin signature in a large set of human cardiac samples and myocardium of animal models with cardiac remodeling caused by pressure overload, myocardial infarction or a gene defect. We studied levels of total, acetylated, and detyrosinated α-tubulin and desmin in cardiac tissue from hypertrophic (HCM...
Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology - August 29, 2023 Category: Physiology Source Type: research

Early onset of urea synthesis and ammonia detoxification pathways in three terrestrially developing frogs
AbstractFrogs evolved terrestrial development multiple times, necessitating mechanisms to avoid ammonia toxicity at early stages. Urea synthesis from ammonia is a key adaptation that reduces water dependence after metamorphosis. We tested for early expression and plasticity of enzymatic mechanisms of ammonia detoxification in three terrestrial-breeding frogs: foam-nest-dwelling larvae ofLeptodactylus fragilis (Lf) and arboreal embryos ofHyalinobatrachium fleischmanni (Hf) andAgalychnis callidryas (Ac). Activity of two ornithine-urea cycle (OUC) enzymes, arginase and CPSase, and levels of their products urea and CP in tissu...
Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology - August 28, 2023 Category: Physiology Source Type: research

Hypoxic incubation at 50% of atmospheric levels shifts the cardiovascular response to acute hypoxia in American alligators, Alligator mississippiensis
AbstractWe designed a series of studies to investigate whether hypoxia (10% O2) from 20% of incubation to hatching, or from 20 to 50% of incubation, affects cardiovascular function when juvenile American alligators reached an age of 4 –5 years compared to juveniles that were incubated in 21% O2. At this age, we measured blood flows in all the major arteries as well as heart rate, blood pressure, and blood gases in animals in normoxia and acute hypoxia (10% O2 and 5% O2). In all three groups, exposure to acute hypoxia of 10% O2 caused a decrease in blood O2 concentration and an increase in heart rate in 4 –5-year-old a...
Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology - August 24, 2023 Category: Physiology Source Type: research

A 108-h total sleep deprivation did not impair fur seal performance in delayed matching to sample task
We examined the effects of a 108-h total sleep deprivation (TSD) on working memory in the northern fur seal, an animal with unusual sleep phenomenology and long-range annual migrations. The performance of fur seals was evaluated in a two-choice visual delayed matching to sample (DMTS) task, which is commonly used to evaluate working memory. In baseline conditions, the performance of fur seals in a DMTS task based on the percentage of errors was somewhat comparable with that in nonhuman primates at similar delays. We have determined that a 108-h TSD did not affect fur seals ’ performance in a visual DMTS task as measured ...
Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology - August 18, 2023 Category: Physiology Source Type: research

The role of octopamine and crustacean hyperglycemic hormone (CHH) in branchial acid –base regulation in the European green crab, Carcinus maenas
AbstractCrustaceans ’ endocrinology is a vastly understudied area of research. The major focus of the studies on this topic to date has been on the molting cycle (and in particular, the role of crustacean hyperglycemic hormone (CHH)), as well as the role of other hormones in facilitating physiological phenotypic adju stments to salinity changes. Additionally, while many recent studies have been conducted on the acclimation and adaptation capacity of crustaceans to a changing environment, only few have investigated internal hormonal balance especially with respect to an endocrine response to environmental challen ges. Con...
Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology - August 10, 2023 Category: Physiology Source Type: research

Chronic hypoxia and hyperoxia alter tissue-specific fatty acid profile and FD6D and elongase gene expression levels in rainbow trout (Oncorhynchus mykiss)
AbstractCommercially important trout species, especially rainbow trout, are under great threat due to several negative factors affecting oxygen levels in water such as global warming and eutrophication. In our study, rainbow trout (Oncorhynchus mykiss) was exposed to chronic (for 28  days) hypoxia (4.0 ± 0.5 mg/L) and hyperoxia (12 ± 1.2 mg/L) in order to evaluate the alteration of fatty acid profiles in muscle, liver and gill tissues. In addition, delta-6-desaturase and elongase gene expression profiles were measured in liver, kidney and gill tissues. The amount o f saturated fatty acids increased by oxygen a...
Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology - August 1, 2023 Category: Physiology Source Type: research

Steroid hormone-dependent changes in trehalose physiology in the silkworm, Bombyx mori
AbstractHolometabolous insects undergo metamorphosis to reconstruct their body to the adult form during pupal period. Since pupae cannot take any diets from the outside because of a hard pupal cuticle, those insects stock up on nutrients sufficient for successful metamorphosis during larval feeding period. Among those nutrients, carbohydrates are stored as glycogen or trehalose, which is the major blood sugar in insects. The hemolymph trehalose is constantly high during the feeding period but suddenly decreases at the beginning of the prepupal period. It is believed that trehalase, which is a trehalose-hydrolyzing enzyme, ...
Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology - August 1, 2023 Category: Physiology Source Type: research

Developmental, physiologic and phylogenetic perspectives on the expression and regulation of myosin heavy chains in mammalian skeletal muscles
AbstractThe kinetics of myosin controls the speed and power of muscle contraction. Mammalian skeletal muscles express twelve kinetically different myosin heavy chain (MyHC) genes which provides a wide range of muscle speeds to meet different functional demands. Myogenic progenitors from diverse craniofacial and somitic mesoderm specify muscle allotypes with different repertoires for MyHC expression. This review provides a brief synopsis on the historical and current views on how cell lineage, neural impulse patterns, and thyroid hormone influence MyHC gene expression in muscles of the limb allotype during development and i...
Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology - August 1, 2023 Category: Physiology Source Type: research

Biochemical response of two earthworm taxa exposed to freezing
In this study, we used1H NMR to investigate metabolomic changes in two freeze-tolerant earthworm taxa,Dendrobaena octaedra and one of the genetic lineages ofEisenia sp. aff.nordenskioldi f.pallida. A total of 45 metabolites were quantified. High concentrations of glucose were present in frozen tissues of both taxa. No other putative cryoprotectants were found. We detected high levels of glycolysis end products and succinate in frozen animals, indicating the activation of glycolysis. Concentrations of many other substances also significantly increased. On the whole, metabolic change in response to freezing was much more pro...
Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology - August 1, 2023 Category: Physiology Source Type: research

Lactating SKH-1 furless mice prioritize own comfort over growth of their pups
AbstractLactation is the most energetically demanding physiological process that occurs in mammalian females, and as a consequence of this energy expenditure, lactating females produce an enormous amount of excess heat. This heat is thought to limit the amount of milk a mother produces, and by improving heat dissipation, females may improve their milk production and offspring quality. Here we used SKH-1 hairless mice as a natural model of improved heat dissipation. Lactating mothers were given access to a secondary cage to rest away from their pups, and this secondary cage was kept either at room temperature (22  °C) in ...
Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology - August 1, 2023 Category: Physiology Source Type: research

Correction to: Mitochondrial volume density and evidence for its role in adaptive divergence in response to thermal tolerance in threespine stickleback
(Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology)
Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology - August 1, 2023 Category: Physiology Source Type: research

The implications of exercise in Drosophila melanogaster: insights into Akt/p38 MAPK/Nrf2 pathway associated with Hsp70 regulation in redox balance maintenance
This study investigated the potential effects of exercise on the responses of energy metabolism, redox balance maintenance, and apoptosis regulation inDrosophila melanogaster to shed more light on the mechanisms underlying the increased performance that this emerging exercise model provides. Three groups were evaluated for seven days: the control (no exercise or locomotor limitations), movement-limited flies (MLF) (no exercise, with locomotor limitations), and EXE (with exercise, no locomotor limitations). The EXE flies demonstrated greater endurance-like tolerance in the swimming test, associated with increased citrate sy...
Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology - July 28, 2023 Category: Physiology Source Type: research

Noradrenergic tone is not required for neuronal activity-induced rebound sleep in zebrafish
AbstractSleep pressure builds during wakefulness, but the mechanisms underlying this homeostatic process are poorly understood. One zebrafish model suggests that sleep pressure increases as a function of global neuronal activity, such as during sleep deprivation or acute exposure to drugs that induce widespread brain activation. Given that the arousal-promoting noradrenergic system is important for maintaining heightened neuronal activity during wakefulness, we hypothesised that genetic and pharmacological reduction of noradrenergic tone during drug-induced neuronal activation would dampen subsequent rebound sleep in zebra...
Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology - July 22, 2023 Category: Physiology Source Type: research