Electron transfer and ROS production in brain mitochondria of intertidal and subtidal triplefin fish (Tripterygiidae)
AbstractWhile oxygen is essential for oxidative phosphorylation, O2 can form reactive species (ROS) when interacting with electrons of mitochondrial electron transport system. ROS is dependent on O2 pressure (PO2) and has traditionally been assessed in O2 saturated media, PO2 at which mitochondria do not typically function in vivo. Mitochondrial ROS can be significantly elevated by the respiratory complex II substrate succinate, which can accumulate within hypoxic tissues, and this is exacerbated further with reoxygenation. Intertidal species are repetitively exposed to extreme O2 fluctuations, and have likely evolved stra...
Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology - May 5, 2023 Category: Physiology Source Type: research

Body mass and cuticular hydrocarbon profiles, but not queen number, underlie worker desiccation resistance in a facultatively polygynous harvester ant (Pogonomyrmex californicus)
AbstractAs small-bodied terrestrial organisms, insects face severe desiccation risks in arid environments, and these risks are increasing under climate change. Here, we investigate the physiological, chemical, and behavioral mechanisms by which harvester ants, one of the most abundant arid-adapted insect groups, cope with desiccating environmental conditions. We aimed to understand how body size, cuticular hydrocarbon profiles, and queen number impact worker desiccation resistance in the facultatively polygynous harvester ant,Pogonomyrmex californicus. We measured survival at 0% humidity of field-collected worker ants sour...
Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology - April 29, 2023 Category: Physiology Source Type: research

Male blue wildebeest increase activity during the rut, but not at the expense of rest
We examined the daily activity and inactivity patterns of dominant bulls by means of actigraphy for 3 months, which included the rut. We also measured faecal androgen metabolite (fAM) levels and subcutaneous temperature, both of which have variances known to delineate the rut. During the rut, wildebeest bulls experienced higher levels of activity, fAM, and a greater daily range of subcutaneous temperature. Despite previous reports, the male blue wildebeest rested daily during the rut, and while the amount of rest was low, it was not substantially lower than prior to the rut. The amount of time spent inactive increased subs...
Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology - April 28, 2023 Category: Physiology Source Type: research

Correction to: An expos é of Frappellian Motion
(Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology)
Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology - April 28, 2023 Category: Physiology Source Type: research

Male blue wildebeest increase activity during the rut, but not at the expense of rest
We examined the daily activity and inactivity patterns of dominant bulls by means of actigraphy for 3 months, which included the rut. We also measured faecal androgen metabolite (fAM) levels and subcutaneous temperature, both of which have variances known to delineate the rut. During the rut, wildebeest bulls experienced higher levels of activity, fAM, and a greater daily range of subcutaneous temperature. Despite previous reports, the male blue wildebeest rested daily during the rut, and while the amount of rest was low, it was not substantially lower than prior to the rut. The amount of time spent inactive increased subs...
Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology - April 28, 2023 Category: Physiology Source Type: research

Correction to: An expos é of Frappellian Motion
(Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology)
Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology - April 28, 2023 Category: Physiology Source Type: research

The rete mirabile: a possible control site for swimbladder function
In this study, the data set was reanalyzed for the presence of receptor proteins and proteins involved in intracellular signaling pathways. A large number of expressed receptor proteins and proteins involved in intracellular signal transduction was detected. Several G-protein-coupled receptor signal pathways were significantly enriched in their expression level, in particular receptors and signaling pathways involved in the control of blood flow. The enriched signaling pathways also include pathways involved in trafficking of crucial transport proteins like, monocarboxylate transporters, V-ATPase, and aquaporin. The data, ...
Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology - April 15, 2023 Category: Physiology Source Type: research

An atlas of plasma-accessible carbonic anhydrase availability in the model teleost, the rainbow trout
AbstractThe unique teleost oxygenation system that permits enhanced oxygen unloading during stress comprises three main characteristics: pH-sensitive haemoglobin, red blood cell (RBC) intracellular pH (pHi) protection, and a heterogeneous distribution of plasma-accessible carbonic anhydrase (paCA). A heterogeneous distribution of paCA is essential; its presence permits enhanced oxygen unloading during stress, while its absence at the gills maintains conditions for oxygen uptake by pH-sensitive haemoglobins. We hypothesised that paCA would be absent in all four gill arches, as has been previously indicated for arch two, and...
Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology - April 8, 2023 Category: Physiology Source Type: research

Blood chemistry and biliverdin differ according to reproduction and tourism in a free-living lizard
AbstractChanges in the physiological health of species are an essential indicator of changing conditions and environmental challenges. Reponses to environmental challenges can often induce stress, influence physiology, and change metabolism in organisms. Here we tested blood chemistry parameters indicative of stress and metabolic activity using an i-STAT point-of-care blood analyzer in seven populations of free-ranging rock iguanas exposed to varying levels of tourism and supplemental feeding. We found significant differences in blood chemistry (glucose, oxygen, carbon dioxide, hematocrit, hemoglobin, calcium, potassium, a...
Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology - March 30, 2023 Category: Physiology Source Type: research

Seasonal flexibility of the gut structure and physiology in Eremias multiocellata
This study reveals the intestinal regulation and adaptation mechanisms inE. multiocellata in response to the hibernation season. (Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology)
Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology - March 30, 2023 Category: Physiology Source Type: research

Blood chemistry and biliverdin differ according to reproduction and tourism in a free-living lizard
AbstractChanges in the physiological health of species are an essential indicator of changing conditions and environmental challenges. Reponses to environmental challenges can often induce stress, influence physiology, and change metabolism in organisms. Here we tested blood chemistry parameters indicative of stress and metabolic activity using an i-STAT point-of-care blood analyzer in seven populations of free-ranging rock iguanas exposed to varying levels of tourism and supplemental feeding. We found significant differences in blood chemistry (glucose, oxygen, carbon dioxide, hematocrit, hemoglobin, calcium, potassium, a...
Source: Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology - March 30, 2023 Category: Physiology Source Type: research