Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology最新文献_第4页

Tissue-specific markers of salinity-induced allostasis in the very euryhaline and widespread mussel Mytilus galloprovincialis 在非常普遍的咸化和广泛的贻贝紫贻贝中，盐度诱导的适应状态的组织特异性标记。

IF 2.2 3区生物学

Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology Pub Date : 2026-01-01 Epub Date: 2025-11-15 DOI: 10.1016/j.cbpa.2025.111954

Nicole Stakowian , Marta Cunha , Rosa Freitas , Carolina A. Freire

{"title":"Tissue-specific markers of salinity-induced allostasis in the very euryhaline and widespread mussel Mytilus galloprovincialis","authors":"Nicole Stakowian , Marta Cunha , Rosa Freitas , Carolina A. Freire","doi":"10.1016/j.cbpa.2025.111954","DOIUrl":"10.1016/j.cbpa.2025.111954","url":null,"abstract":"<div><div>Environmental salinity is one of the main factors causing osmotic stress in coastal bivalves, influencing their physiological performance and distribution. The Mediterranean mussel <em>Mytilus galloprovincialis</em> is one of the most euryhaline marine invertebrates, tolerating large salinity fluctuations throughout its wide geographical distribution. This study investigated how different tissues respond to different salinities, identifying potential biochemical markers of tolerance and plasticity. Mussels were exposed for 14 and 28 days to the salinities 20, 25, 30, 35, and 40, and biomarkers related to metabolism, antioxidant and biotransformation systems, cellular damage, and neurotoxicity were analyzed in the digestive gland, gills, mantle, and muscle. The digestive gland showed significant modulation of succinate dehydrogenase, superoxide dismutase and carboxylesterases activities, glycogen content, and antioxidant capacity, demonstrating its metabolic and antioxidant role. The gills showed changes in glutathione S-transferases, acetylcholinesterase, and lipid peroxidation levels, particularly under hyposaline (20) and hypersaline (40) conditions. Mantle and muscle showed lower responsiveness to the tested salinities. Biochemical responses at salinities between 25 and 35 indicated the activation of allostatic mechanisms assuring survival and damage prevention. The results corroborate the concept of salinity-induced allostasis as a mechanism of resistance in osmoconforming euryhaline bivalves. Furthermore, they highlight the importance of functional compartmentalization among tissues in responding to osmotic challenges. The results also support the use of organ-level biomarkers to assess physiological resistance to salinity gradients in coastal environments.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"311 ","pages":"Article 111954"},"PeriodicalIF":2.2,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145535155","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Body mass shapes mitochondrial NADH and NADPH sources in mammalian skeletal muscle 体重影响哺乳动物骨骼肌线粒体NADH和NADPH来源

IF 2.2 3区生物学

Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology Pub Date : 2026-01-01 Epub Date: 2025-10-25 DOI: 10.1016/j.cbpa.2025.111944

Mélanie Boël , Yann Voituron , Damien Roussel

引用次数: 0

Effects of chronic salinity stress on growth performance, physiological response and intestinal microbiota of largemouth bass (Micropterus salmoides) 慢性盐度胁迫对大口黑鲈生长性能、生理反应和肠道菌群的影响

IF 2.2 3区生物学

Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology Pub Date : 2026-01-01 Epub Date: 2025-11-07 DOI: 10.1016/j.cbpa.2025.111945

Yang Liu , Jing Tian , Shengjie Li , Tao Zhu , Jinxing Du , Caixia Lei , Linqiang Han , Hongmei Song

{"title":"Effects of chronic salinity stress on growth performance, physiological response and intestinal microbiota of largemouth bass (Micropterus salmoides)","authors":"Yang Liu , Jing Tian , Shengjie Li , Tao Zhu , Jinxing Du , Caixia Lei , Linqiang Han , Hongmei Song","doi":"10.1016/j.cbpa.2025.111945","DOIUrl":"10.1016/j.cbpa.2025.111945","url":null,"abstract":"<div><div>To address the critical shortage of freshwater in global fisheries, the cultivation of largemouth bass (<em>Micropterus salmoides</em>) using geographically widespread saline-alkaline water is a viable resource alternative. In the present study, we systematically investigated the effects of chronic salinity stress (180 days, 9 ppt) on the growth performance, osmoregulation, antioxidant capacity, digestion capacity, and intestinal microbiota of largemouth bass. The results showed that the growth performance (CF, ADG, and SGR) of largemouth bass in the saltwater group decreased significantly compared with the freshwater group after 180 days of culture. The osmoregulation capacity (serum osmolality, serum cortisol, NKA, and CMA) and antioxidant capacity (SOD, CAT, MDA, ACP, AKP, and GSH-Px) in the saltwater group were significantly higher than those in the freshwater group at 60d, 120d, and 180d (<em>P</em> < 0.05). Histological analysis showed that chlorine cells and macrophages proliferated in the gill and liver of the saltwater group. Additionally, trypsin and pancreatic lipase levels in the saltwater group peaked on 180 days, but remained significantly lower than those in the freshwater group (<em>P</em> < 0.05). According to intestinal microbiota analysis, the relative abundance of Bacillus and Cetobacterium in the saltwater group was significantly higher than that in the freshwater group (<em>P</em> < 0.05). The above results indicated that largemouth bass showed excellent stress resistance in the face of chronic salinity stress, which could be used as a saline-alkali culture species. The work provides new insights for the study of salt tolerance in freshwater fish and promotes the utilization of saline-alkali water.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"311 ","pages":"Article 111945"},"PeriodicalIF":2.2,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145477262","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

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Seasonal adjustments of basal metabolism and substrate metabolism in an Asian passerine bird, the red-billed leiothrix 一种亚洲雀形目鸟类的基础代谢和底物代谢的季节调整。

IF 2.2 3区生物学

Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology Pub Date : 2026-01-01 Epub Date: 2025-11-07 DOI: 10.1016/j.cbpa.2025.111950

Xing-Rong He , Xiao-Lin Zhu , Zi-Qing Gao , Qi Zheng , Shou-Hui Wang , Zhe Wang , Ming Li , Jin-Song Liu

{"title":"Seasonal adjustments of basal metabolism and substrate metabolism in an Asian passerine bird, the red-billed leiothrix","authors":"Xing-Rong He , Xiao-Lin Zhu , Zi-Qing Gao , Qi Zheng , Shou-Hui Wang , Zhe Wang , Ming Li , Jin-Song Liu","doi":"10.1016/j.cbpa.2025.111950","DOIUrl":"10.1016/j.cbpa.2025.111950","url":null,"abstract":"<div><div>Phenotypic flexibility enables organisms like birds to adapt to environmental changes, particularly through physiological adjustments such as basal metabolism in response to temperature fluctuations. We have previously reported that red-billed leiothrix (<em>Leiothrix lutea</em>) increases basal metabolism when acclimated to cold temperatures in the lab. This study investigated whether similar physiological changes also occur in response to seasonal variations in the wild. Red-billed leiothrixes were captured in different seasons in Wenzhou and subjected to experiments that measured body mass, metabolic parameters such as basal metabolic rate (BMR), cytochrome <em>c</em> oxidase (COX), substrates of metabolism such as serum glucose, hepatic glycogen, and muscle glycogen, triglyceride (TG), free fatty acid (FFA), enzymes such as carnitine palmitoyl transferase-1 (CPT-1), β-hydroxyacyl Co-A dehydrogenase (HOAD), and citrate synthase (CS), and thyroid hormones (T<sub>4</sub>, thyroxine, and T<sub>3</sub>, triiodothyronine). In winter, the birds showed significant increases in body mass, BMR, and COX activity in the liver and kidney compared to summer. Additionally, serum TG, concentration of CPT-1 and HOAD in the liver, serum glucose, and muscle glycogen were also elevated. These results were consistent with enhanced metabolism and higher consumption of lipids by red-billed leiothrixes during winter compared with other seasons. Therefore, red-billed leiothrixes show the same pattern of phenotypic flexibility as thermally acclimated birds in the lab. This study provides valuable data for understanding basal metabolism in small birds in response to seasonal changes.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"311 ","pages":"Article 111950"},"PeriodicalIF":2.2,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145484000","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Context-dependent relationships between metabolism and behavior across temperature acclimations in sheepshead minnows (Cyprinodon variegatus) 在温度适应过程中，羊头鲦鱼的代谢和行为之间的环境依赖关系。

IF 2.2 3区生物学

Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology Pub Date : 2026-01-01 Epub Date: 2025-11-17 DOI: 10.1016/j.cbpa.2025.111952

Madison Schumm, Kerri L. Ackerly, Andrew J. Esbaugh

{"title":"Context-dependent relationships between metabolism and behavior across temperature acclimations in sheepshead minnows (Cyprinodon variegatus)","authors":"Madison Schumm, Kerri L. Ackerly, Andrew J. Esbaugh","doi":"10.1016/j.cbpa.2025.111952","DOIUrl":"10.1016/j.cbpa.2025.111952","url":null,"abstract":"<div><div>Marine fish are able to cope with environmental changes through altering their physiology and behavior. Among environmental stressors, thermal stress is particularly relevant for fish because increased temperature leads to elevated baseline metabolic costs and also has known impacts on behavior. The Performance Model provides a conceptual framework linking metabolism and behavior such that individual differences in baseline metabolic demand influence behavioral expression specifically related to acquiring resources that support metabolic machinery. Thus, under warming, increased energy demand should lead to increased risk-taking and lower behaviors that deter predation (e.g., shoaling and scototaxis). On this background, our objective was to assess behavioral and metabolic responses to warming and the relationship these traits across two temperatures in an estuarine model teleost, the sheepshead minnow (<em>Cyprinodon variegatus</em>). Fish were exposed to 22 °C or 32 °C for 14-days and standard metabolic rate (SMR) was measured. Each fish was subsequently tested in a series of behavioral assays to assess activity, exploration, sociability, and anxiety-like behavior. As anticipated, warmer temperatures increased in SMR and increased activity while reducing anxiety-like behavior. However, relationships between behavior and metabolism were present only in control conditions and, composite behavioral scores indicated negative relationships in in the opposite direction of predictions based on the performance model. Interestingly, trait patterns dissipated under warming suggesting that predictions based on models in control conditions may have dubious utility under climate change. We argue that behavioral-metabolic relationships are sensitive to context, and environmental factors should be considered when exploring the intersection between behavior and physiology.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"311 ","pages":"Article 111952"},"PeriodicalIF":2.2,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145558325","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Heat shock protein 70 expression in the skin of Pelophylax bergeri in response to thermal stress 热休克蛋白70在柏草表皮对热应激的表达。

IF 2.2 3区生物学

Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology Pub Date : 2026-01-01 Epub Date: 2025-11-16 DOI: 10.1016/j.cbpa.2025.111955

Francesca Simoncelli , Ines Di Rosa , Anna Fagotti

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Key indicators of metabolic activity in the long-tailed ground squirrels, (Urocitellus undulatus) in different functional states 不同功能状态下长尾地松鼠代谢活性的关键指标。

IF 2.2 3区生物学

Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology Pub Date : 2026-01-01 Epub Date: 2025-11-15 DOI: 10.1016/j.cbpa.2025.111953

Polina O. Teplova , Ekaterina V. Kuznetsova , Aleksandra V. Gorbunova , Liubov N. Markevich , Nadezhda M. Zakharova

{"title":"Key indicators of metabolic activity in the long-tailed ground squirrels, (Urocitellus undulatus) in different functional states","authors":"Polina O. Teplova , Ekaterina V. Kuznetsova , Aleksandra V. Gorbunova , Liubov N. Markevich , Nadezhda M. Zakharova","doi":"10.1016/j.cbpa.2025.111953","DOIUrl":"10.1016/j.cbpa.2025.111953","url":null,"abstract":"<div><div>The aim of this study is to examine the seasonal strategies employed by obligate hibernators, such as long-tailed ground squirrels (<em>Urocitellus undulatus</em>), for metabolic maintenance at various levels of organization. To this end, we conducted a comprehensive evaluation encompassing respirometry, histological and biochemical analysis of the thyroid gland, examination of neutral and phospholipid content in brown adipose tissue, and biochemical assessment of the blood lipid profile. Our results revealed pronounced variations in metabolic parameters on a seasonal basis. In the fall (pre-hibernation), <em>U. undulatus</em> exhibited an increase in respiratory metabolism ranging from 1.4 to 1.7 times compared to the summer control group. It is accompanied with an augmentation in the functional activity of the thyroid gland, an increase in all fractions of phospholipids in brown adipose tissue, and an elevation in the level of lipase in the blood. Concurrently, there is a decline in di- and triglyceride levels in brown fat. In a state of torpor, there was an observed increase in the growth of certain indicators (lipids, thyroid hormones, etc.), a particularly significant rise is observed for β-hydroxybutyrate. In the interbout euthermia, a recovery of nearly all indicators to summer-fall values was observed. These findings hold potential relevance for a better understanding of metabolic disorders and adaptations to extreme conditions.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"311 ","pages":"Article 111953"},"PeriodicalIF":2.2,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145544008","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Arctic seabirds exposed to acute stress display state- and environment-dependent patterns of surface temperature change, independent of mercury contamination 北极海鸟暴露于急性应激显示状态和环境依赖模式的表面温度变化，独立于汞污染。

IF 2.2 3区生物学

Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology Pub Date : 2026-01-01 Epub Date: 2025-11-08 DOI: 10.1016/j.cbpa.2025.111948

Melissa L. Grunst , Andrea S. Grunst , David Grémillet , Manon Amiguet , Julie Charrier , Marta Cruz-Flores , Thomas Lacoue-Labarthe , Jérôme Fort

{"title":"Arctic seabirds exposed to acute stress display state- and environment-dependent patterns of surface temperature change, independent of mercury contamination","authors":"Melissa L. Grunst , Andrea S. Grunst , David Grémillet , Manon Amiguet , Julie Charrier , Marta Cruz-Flores , Thomas Lacoue-Labarthe , Jérôme Fort","doi":"10.1016/j.cbpa.2025.111948","DOIUrl":"10.1016/j.cbpa.2025.111948","url":null,"abstract":"<div><div>Animals mount a suite of physiological reactions when confronted with acute stressors, including changes in body temperature (T<sub>b</sub>). Such thermal stress responses (TSRs) are important to survival, but may also generate heat stress, making regulation critical. Poor body condition and exposure to chemical contaminants, such as mercury (Hg), a neurotoxin and endocrine disruptor, may have physiological effects that disrupt modulation of TSRs. Implications of such effects could be magnified by climate change. We used infrared thermography (IRT) imagery to measure stress-induced changes in body surface temperature (maximum temperature of the eye region; T<sub>EYE</sub>) of an Arctic seabird, the little auk (<em>Alle alle</em>). We evaluated how changes were correlated with Hg contamination, body condition, blood chemistry parameters and ambient temperature (T<sub>a</sub>). As Arctic animals, little auks are cold-adapted and face warming rates nearly four times the global average, making them vulnerable to heat stress. Little auks displayed a robust TSR with T<sub>EYE</sub> at sample point 1–3 (mean ± SD) of 28.9 ± 6.86 °C, 33.7 ± 5.48 °C, and 35.4 ± 5.76 °C, respectively. Mercury load was unrelated to changes in T<sub>EYE</sub>. However, T<sub>EYE</sub> was elevated at higher T<sub>a</sub> (β ± SE =3.214 ± 0.733) across sampling time points, suggesting upregulation of heat dissipation. Furthermore, little auks in poor condition displayed lower magnitude changes in T<sub>EYE</sub> (β ± SE = 0.688 ± 0.232), and several blood chemistry parameters were correlated to changes in T<sub>EYE</sub>. Results suggest that thermoregulatory dynamics in the face of acute stress depend on environmental and physiological state.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"311 ","pages":"Article 111948"},"PeriodicalIF":2.2,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145490955","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Gastrointestinal effects of crustacean shell by-products in diets for farmed Atlantic cod (Gadus morhua) 养殖大西洋鳕鱼（Gadus morhua）日粮中甲壳类副产品对胃肠的影响。

IF 2.2 3区生物学

Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology Pub Date : 2026-01-01 Epub Date: 2025-11-13 DOI: 10.1016/j.cbpa.2025.111951

Martina Quagliardi , Trond M. Kortner , André S. Bogevik , Elvis Chikwati , Kathrine Ryvold Bakkemo , Elin Christine Valen , Ellen Elisabeth K. Hage , Guro Løkka

{"title":"Gastrointestinal effects of crustacean shell by-products in diets for farmed Atlantic cod (Gadus morhua)","authors":"Martina Quagliardi , Trond M. Kortner , André S. Bogevik , Elvis Chikwati , Kathrine Ryvold Bakkemo , Elin Christine Valen , Ellen Elisabeth K. Hage , Guro Løkka","doi":"10.1016/j.cbpa.2025.111951","DOIUrl":"10.1016/j.cbpa.2025.111951","url":null,"abstract":"<div><div>By-products from crustaceans destined for human consumption are often discarded but may serve as sustainable aqua-feed ingredients. This study assessed short-term physiological responses in Atlantic cod (<em>Gadus morhua</em>) when 15 % sunflower meal in commercial diets was replaced with 15 % brown crab (<em>Cancer pagurus</em>) or 10 % shrimp (<em>Pandalus borealis</em>) shell meals. In a 27-day trial, cod (∼300 g) in triplicate 500 l tanks (<em>n</em> = 29–36) were fed isoenergetic diets. Growth, feed intake, distal intestinal (DI) dry matter, amino acid digestibility, and mineral content were measured, alongside gastrointestinal macro- and microanatomy, digestive enzymes, bile salts, and gut gene expression.</div><div>Diet had no significant effect on feed intake or growth. Crab shell meal (CSM) increased DI calcium (13 % vs. 3 %), dry matter (24 % vs. 15–19 %), and amino acid digestibility (91 % vs. 89 %), while reducing dry matter digestibility (57 % vs. 66–68 %) and trypsin activity. In the pyloric caeca (PC), CSM-fed fish had the highest bile salt level and maltase capacity. Sunflower meal increased DI lamina propria cellularity, DI iron and copper, while shrimp shell meal increased DI phosphorus (2.4 % vs. 1.3 %). Bile salts, trypsin, maltase, and LAP activity peaked in the PC and decreased distally. Relative intestinal length correlated with fish weight (<em>r</em> = 0.53, <em>P</em> < 0.001). Pancreatic digestive enzyme genes and osmoregulatory genes (<em>atp1a1</em>, <em>aqp8</em>) peaked in PC, whereas <em>slc26a6</em> expression was negligible throughout.</div><div>Crustacean shell meals are promising as sustainable feed ingredients for Atlantic cod, and the study offers novel insights into gut structure and function with implications for intestinal health in farmed cod.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"311 ","pages":"Article 111951"},"PeriodicalIF":2.2,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145531050","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Hyperoxia acclimation and the aerobic response in red drum (Sciaenops ocellatus) 红鼓鱼的高氧驯化和有氧反应。

IF 2.2 3区生物学

Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology Pub Date : 2026-01-01 Epub Date: 2025-11-07 DOI: 10.1016/j.cbpa.2025.111949

Benjamin Negrete Jr , Kerri Lynn Ackerly , Madison R. Schumm , Andrew J. Esbaugh

{"title":"Hyperoxia acclimation and the aerobic response in red drum (Sciaenops ocellatus)","authors":"Benjamin Negrete Jr , Kerri Lynn Ackerly , Madison R. Schumm , Andrew J. Esbaugh","doi":"10.1016/j.cbpa.2025.111949","DOIUrl":"10.1016/j.cbpa.2025.111949","url":null,"abstract":"<div><div>Hyperoxia is supersaturation of oxygen beyond 100 % air saturation (∼21 kPa) in aquatic environments. Hyperoxia promotes an oxygen diffusion gradient that greatly increases arterial and venous oxygen in the circulatory system of fish. Under these conditions fish can potentially upregulate mechanisms that benefit from supersaturation by increasing oxygen use and delivery. To test this, we acclimated the estuarine red drum (<em>Sciaenops ocellatus</em>) to three weeks of normoxic control (100 % air saturation, ∼20.7 kPa) or hyperoxic treatment (150 % air saturation, ∼32.5 kPa). We measured whole-animal metabolic rate in a cross design to assess aerobic scope and observed oxygen supply capacity, α<sub>o</sub>. Following recovery, fish were sampled for magnitude of the Root effect and mitochondrial respiration of cardiac tissue. Red drum acclimated to hyperoxia showed lower mean cell hemoglobin content, decreased methemoglobin, and a modest decrease in red blood cell pH. The Root effect, the pH sensitivity that limits carrying capacity, was measured to ascertain differences in O<sub>2</sub> delivery in the heart; however, we found no differences due to acclimation. Cardiac mitochondria respiration showed no difference between acclimations. Acclimation did not impact whole-animal metabolic rate. However, fish from both acclimations increased maximum metabolic rate when exhaustively exercised in hyperoxia, which subsequently increased aerobic scope. Measures of α calculated at maximum metabolic rate and at the critical oxygen tension (P<sub>crit</sub>) showed that α was lower when calculated in hyperoxia than normoxia or at P<sub>crit</sub>. These data suggest that fish can benefit from hyperoxia in acute exposures, with subtle adjustments made in chronic hyperoxia.</div></div>","PeriodicalId":55237,"journal":{"name":"Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology","volume":"311 ","pages":"Article 111949"},"PeriodicalIF":2.2,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145483922","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0