THE EGYPTIAN JOURNAL OF EXPERIMENTAL BIOLOGY最新文献_第3页

Is vertebral shape variability in caecilians (Amphibia: Gymnophiona) constrained by forces experienced during burrowing? 无尾螈(两栖类:裸鱼纲)的椎体形状变异性是否受到挖洞过程中所经历的力的限制?

THE EGYPTIAN JOURNAL OF EXPERIMENTAL BIOLOGY Pub Date : 2022-06-06 DOI: 10.1242/jeb.244288

Aurélien Lowie, B. De Kegel, M. Wilkinson, J. Measey, J. C. O’Reilly, N. Kley, P. Gaucher, J. Brecko, T. Kleinteich, D. Adriaens, A. Herrel

{"title":"Is vertebral shape variability in caecilians (Amphibia: Gymnophiona) constrained by forces experienced during burrowing?","authors":"Aurélien Lowie, B. De Kegel, M. Wilkinson, J. Measey, J. C. O’Reilly, N. Kley, P. Gaucher, J. Brecko, T. Kleinteich, D. Adriaens, A. Herrel","doi":"10.1242/jeb.244288","DOIUrl":"https://doi.org/10.1242/jeb.244288","url":null,"abstract":"Caecilians are predominantly burrowing, elongate, limbless amphibians that remain relatively poorly studied. Although it has been suggested that the sturdy and compact skulls of caecilians are an adaptation to their head-first burrowing habits, no clear relationship between skull shape and burrowing performance appears to exist. However, the external forces encountered during burrowing are transmitted by the skull to the vertebral column, and as such, may impact vertebral shape. Additionally, the muscles that generate the burrowing forces attach onto the vertebral column and consequently may impact vertebral shape that way as well. Here, we explore the relationships between vertebral shape and maximal in vivo push forces in 13 species of caecilian amphibians. Our results show that the shape of the two most anterior vertebrae, as well as the shape of the vertebrae at 90% of the total body length, are not correlated with peak push forces. Conversely, the shape of the third vertebrae, and the vertebrae at 20% and 60% of the total body length, do show a relationship to push forces measured in vivo. Whether these relationships are indirect (external forces constraining shape variation) or direct (muscles forces constraining shape variation) remains unclear and will require quantitative studies of the axial musculature. Importantly, our data suggest that mid-body vertebrae may potentially be used as proxies to infer burrowing capacity in fossil representatives.","PeriodicalId":22458,"journal":{"name":"THE EGYPTIAN JOURNAL OF EXPERIMENTAL BIOLOGY","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79568205","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Mild hypoxia exposure impacts peripheral serotonin uptake and degradation in Gulf toadfish, Opsanus beta. 轻度缺氧暴露影响外周血清素摄取和降解海湾蟾蜍鱼，Opsanus β。

THE EGYPTIAN JOURNAL OF EXPERIMENTAL BIOLOGY Pub Date : 2022-06-06 DOI: 10.1242/jeb.244064

John Sebastiani, Allyson Sabatelli, M. McDonald

{"title":"Mild hypoxia exposure impacts peripheral serotonin uptake and degradation in Gulf toadfish, Opsanus beta.","authors":"John Sebastiani, Allyson Sabatelli, M. McDonald","doi":"10.1242/jeb.244064","DOIUrl":"https://doi.org/10.1242/jeb.244064","url":null,"abstract":"Plasma 5-HT homeostasis is maintained through the combined processes of uptake (via the 5-HT transporter SERT, and others), degradation (via monoamine oxidase, MAO), and excretion. Previous studies have shown that inhibiting SERT, which would inhibit 5-HT uptake and degradation, attenuates parts of the cardiovascular hypoxia reflex in Gulf toadfish (Opsanus beta), suggesting that these 5-HT clearance processes may be important during hypoxia exposure. Therefore, the goal of this experiment was to determine the effects of mild hypoxia on 5-HT uptake and degradation in the peripheral tissues of toadfish. We hypothesized that 5-HT uptake and degradation would be upregulated during hypoxia resulting in lower plasma 5-HT, with uptake occurring in the gill, heart, liver, and kidney. Fish were exposed to normoxia (97.6% O2 saturation, 155.6 torr), or 2-min, 40-min or 24 h mild hypoxia (50% O2 saturation, ∼80 torr), injected with radiolabeled [3H]5-HT and blood, urine, bile and tissues taken. Plasma 5-HT levels were reduced by 40% after 40 min of hypoxia exposure and persisted through 24 h. 5-HT uptake by the gill was upregulated following 2 min of hypoxia exposure, and degradation in the gill was upregulated at 40 min and 24 h. Interestingly, there was no change in 5-HT uptake by the heart and degradation in the heart decreased by 58% within 2 min of hypoxia exposure and by 85% at 24 h. These results suggest that 5-HT clearance is upregulated during hypoxia and is likely driven, in part, by mechanisms within the gill and not the heart.","PeriodicalId":22458,"journal":{"name":"THE EGYPTIAN JOURNAL OF EXPERIMENTAL BIOLOGY","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-06-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81959105","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Cardiac mitochondrial energetics of the Australasian red spiny lobster, Jasus edwardsii, when exposed to isoeugenol within the commercial anaesthetic AQUI-S. 当暴露于商业麻醉剂AQUI-S中的异丁香酚时，澳大拉西亚红刺龙虾的心脏线粒体能量变化。

THE EGYPTIAN JOURNAL OF EXPERIMENTAL BIOLOGY Pub Date : 2022-06-01 DOI: 10.1242/jeb.242771

James A. Robertson, A. Jeffs, C. Hedges, A. Hickey

{"title":"Cardiac mitochondrial energetics of the Australasian red spiny lobster, Jasus edwardsii, when exposed to isoeugenol within the commercial anaesthetic AQUI-S.","authors":"James A. Robertson, A. Jeffs, C. Hedges, A. Hickey","doi":"10.1242/jeb.242771","DOIUrl":"https://doi.org/10.1242/jeb.242771","url":null,"abstract":"The anaesthetic isoeugenol has been used as metabolic suppressant for commercial transport of live lobsters in order to decrease energy expenditure aand improve survival. Given the central role of mitochondria in metabolism and structural similarities of isoeugenol to the mitochondrial electron carrier coenzyme Q, we explored the influence on mitochondrial function of isoeugenol. Mitochondrial function was measured using high resolution respirometry and saponin permeabilized heart fibres from the Australasian red spiny lobster, Jasus edwardsii. Relative to vehicle (polysorbate), isoeugenol inhibited respiration supported by complex I (CI) and cytochrome c oxidase (CCO). While complex II (CII), which also reduces coenzyme Q was largely unaffected by isoeugenol, respiration supported by CII when uncoupled was depressed. Titration of isoeugenol indicates that respiration through CI has a half inhibition constant (IC50) of 2.4±0.1 µM, and full inhibition constant IC100 of approximately 6.3 µM. These concentrations are consistent with those used for transport and euthanasia of J. edwardsii and indicates that CI is a possible target of isoeugenol like many other anaesthetics with quinone-like structures.","PeriodicalId":22458,"journal":{"name":"THE EGYPTIAN JOURNAL OF EXPERIMENTAL BIOLOGY","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85410337","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Understanding how variable thermal environments affect the molecular mechanisms underlying temperature-sensitive phenotypes: lessons from sex determination. 了解不同的热环境如何影响温度敏感表型的分子机制:来自性别决定的教训。

THE EGYPTIAN JOURNAL OF EXPERIMENTAL BIOLOGY Pub Date : 2022-06-01 DOI: 10.1242/jeb.242373

R. Paitz, Anthony T Breitenbach, Rosario A. Marroquín-Flores, R. Bowden

{"title":"Understanding how variable thermal environments affect the molecular mechanisms underlying temperature-sensitive phenotypes: lessons from sex determination.","authors":"R. Paitz, Anthony T Breitenbach, Rosario A. Marroquín-Flores, R. Bowden","doi":"10.1242/jeb.242373","DOIUrl":"https://doi.org/10.1242/jeb.242373","url":null,"abstract":"The thermal environment that organisms experience can affect many aspects of their phenotype. As global temperatures become more unpredictable, it is imperative that we understand the molecular mechanisms by which organisms respond to variable, and often transient, thermal environments. Beyond deciphering the mechanisms through which organisms respond to temperature, we must also appreciate the underlying variation in temperature-dependent processes, as this variation is essential for understanding the potential to adapt to changing climates. In this Commentary, we use temperature-dependent sex determination as an example to explore the mechanistic processes underlying the development of temperature-sensitive phenotypes. We synthesize the current literature on how variable thermal conditions affect these processes and address factors that may limit or allow organisms to respond to variable environments. From these examples, we posit a framework for how the field might move forward in a more systematic way to address three key questions: (1) which genes directly respond to temperature-sensitive changes in protein function and which genes are downstream, indirect responders?; (2) how long does it take different proteins and genes to respond to temperature?; and (3) are the experimental temperature manipulations relevant to the climate the organism experiences or to predicted climate change scenarios? This approach combines mechanistic questions (questions 1 and 2) with ecologically relevant conditions (question 3), allowing us to explore how organisms respond to transient thermal environments and, thus, cope with climate change.","PeriodicalId":22458,"journal":{"name":"THE EGYPTIAN JOURNAL OF EXPERIMENTAL BIOLOGY","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85830457","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Correction: Genetic variation in haemoglobin is associated with evolved changes in breathing in high-altitude deer mice. 更正:血红蛋白的遗传变异与高海拔鹿鼠呼吸的进化变化有关。

THE EGYPTIAN JOURNAL OF EXPERIMENTAL BIOLOGY Pub Date : 2022-06-01 DOI: 10.1242/jeb.244608

C. Ivy, Oliver H. Wearing, Chandrasekhar Natarajan, R. Schweizer, Natalia Gutiérrez‐Pinto, Jonathan P. Velotta, Shane C. Campbell-Staton, Elin E. Petersen, A. Fago, Z. Cheviron, Jay F. Storz, G. Scott

引用次数: 0

Rapid cold hardening increases axonal Na+/K+-ATPase activity and enhances performance of a visual motion detection circuit in Locusta migratoria. 快速冷硬化增加了迁徙蝗轴突Na+/K+- atp酶活性，增强了视觉运动检测电路的性能。

THE EGYPTIAN JOURNAL OF EXPERIMENTAL BIOLOGY Pub Date : 2022-06-01 DOI: 10.1242/jeb.244097

R. Robertson, C. Moyes

引用次数: 4

Siberian hamsters nonresponding to short photoperiod use fasting-induced torpor. 西伯利亚仓鼠对短光周期无反应，采用禁食引起的麻木。

THE EGYPTIAN JOURNAL OF EXPERIMENTAL BIOLOGY Pub Date : 2022-05-26 DOI: 10.1242/jeb.244222

Anna S. Przybylska-Piech, M. Jefimow

引用次数: 3

Influence of caste and subcaste characteristics in ant locomotion (Camponotus fellah). 蚁群和亚蚁群特征对蚁群运动的影响。

THE EGYPTIAN JOURNAL OF EXPERIMENTAL BIOLOGY Pub Date : 2022-05-26 DOI: 10.1242/jeb.243776

Johanna Tross, H. Wolf, S. Pfeffer

{"title":"Influence of caste and subcaste characteristics in ant locomotion (Camponotus fellah).","authors":"Johanna Tross, H. Wolf, S. Pfeffer","doi":"10.1242/jeb.243776","DOIUrl":"https://doi.org/10.1242/jeb.243776","url":null,"abstract":"Worker polymorphism in ants has evolved repeatedly, with considerable differences in the morphometry of worker subcastes. Such body size differences and especially caste- and subcaste-specific characteristics might significantly influence locomotion. Therefore, we performed a comprehensive locomotion analysis along gradients in both body size and walking speed of Camponotus fellah worker subcastes, and of males, which have rarely been studied to date due to short life spans associated with mating flights. We provide a detailed description of the morphometry and size differences of C. fellah castes and subcastes and analyse locomotion in the different polymorphic groups in terms of absolute and relative walking speeds (mesosoma lengths per second). Our results reveal that body size and shape affect locomotion behaviour to different extents in the worker subcastes (minor workers, medias, major workers) and in males. Nevertheless, C. fellah ants use the same overall locomotion strategy, with males and major workers reaching considerably lower walking speeds than minors and medias. Body size thus mainly affects walking speed. Minor workers reach the highest relative velocities by high relative stride lengths in combination with large vertical and lateral COM oscillations and clearly higher stride frequencies of up to 25 Hz. Locomotion of males was characterised by clearly lower walking speeds, wider footprint positions, significant phase shifts and a notable dragging of the shorter hind legs. However, general walking parameters of males differed less from those of the female workers than expected due to division of labour in the colony.","PeriodicalId":22458,"journal":{"name":"THE EGYPTIAN JOURNAL OF EXPERIMENTAL BIOLOGY","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84356255","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Exercise and emersion in air, and recovery in seawater in the green crab (Carcinus maenas): metabolic, acid-base, cardio-ventilatory, and ionoregulatory responses. 绿蟹(Carcinus maenas)的运动、在空气中浸泡和在海水中恢复:代谢、酸碱、心肺和离子调节反应。

THE EGYPTIAN JOURNAL OF EXPERIMENTAL BIOLOGY Pub Date : 2022-05-23 DOI: 10.1242/jeb.244268

C. Wood, B. Po

{"title":"Exercise and emersion in air, and recovery in seawater in the green crab (Carcinus maenas): metabolic, acid-base, cardio-ventilatory, and ionoregulatory responses.","authors":"C. Wood, B. Po","doi":"10.1242/jeb.244268","DOIUrl":"https://doi.org/10.1242/jeb.244268","url":null,"abstract":"In nature, the green crab exhibits emersion and terrestrial activity at low tide. Treadmill exercise in air (20-23°C) of crabs acclimated to 32ppt seawater (13°C) revealed an inverse relationship between velocity and duration: 2.0 BL sec-1sustainable for several minutes, and 0.25 BL sec-1 for long periods. Fatigue was not due to dehydration. Physiological responses over 18-h recovery in seawater after near-exhaustive exercise (0.25 BL sec-1, 1h) in air were compared with responses after quiet emersion (1h) in air. Exercising crabs exhibited transient scaphognathite slowing and progressive increases in heart rate, whereas emersed crabs exhibited persistent inhibition of ventilation and transient heart slowing. Upon return to seawater, all these rates increased above both control and treatment levels. Post-exercise disturbances were more marked and/or longer lasting (e.g. EPOC, hyperventilation, tachycardia, metabolic acidosis, lactate elevation, ionic disturbances) than those after simple air exposure. However, an increase in net acidic equivalent excretion to the environment occurred after emersion but not after exercise. Instead, post-exercise crabs relied on carapace buffering, signaled by elevated haemolymph Ca2+ and Mg2+. Prolonged lowering of haemolymph PCO2 associated with hyperventilation also played a key role in acid-base recovery. EPOC after exercise was 3-fold greater than after emersion, sufficient to support control M˙O2for>14h. This reflected clearance of a large lactate load, likely by glycogen re-synthesis rather than oxidation. We conclude that the amphibious green crab uses a combination of aquatic and terrestrial strategies to support exercise in air, emersion in air, and recovery in seawater.","PeriodicalId":22458,"journal":{"name":"THE EGYPTIAN JOURNAL OF EXPERIMENTAL BIOLOGY","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73503917","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Accelerating animal energetics: High dive costs in a small seabird disrupt the dynamic body acceleration - energy expenditure relationship. 加速动物能量:小海鸟的高潜水成本破坏了动态身体加速-能量消耗关系。

THE EGYPTIAN JOURNAL OF EXPERIMENTAL BIOLOGY Pub Date : 2022-05-20 DOI: 10.1242/jeb.243252

Eric Ste Marie, D. Grémillet, J. Fort, A. Patterson, Émile Brisson‐Curadeau, M. Clairbaux, Samuel Perret, J. Speakman, K. Elliott

{"title":"Accelerating animal energetics: High dive costs in a small seabird disrupt the dynamic body acceleration - energy expenditure relationship.","authors":"Eric Ste Marie, D. Grémillet, J. Fort, A. Patterson, Émile Brisson‐Curadeau, M. Clairbaux, Samuel Perret, J. Speakman, K. Elliott","doi":"10.1242/jeb.243252","DOIUrl":"https://doi.org/10.1242/jeb.243252","url":null,"abstract":"Accelerometry has been widely used to estimate energy expenditure in a broad array of terrestrial and aquatic species. However, a recent reappraisal of the method showed that relationships between dynamic body acceleration (DBA) and energy expenditure weaken as the proportion of non-mechanical costs increase. Aquatic air breathing species often exemplify this pattern, as buoyancy, thermoregulation and other physiological mechanisms disproportionately affect oxygen consumption during dives. Combining biologging with the doubly-labelled water method, we simultaneously recorded daily energy expenditure (DEE) and triaxial acceleration in one of the world's smallest wing-propelled breath-hold divers, the dovekie (Alle alle). These data were used to estimate the activity-specific costs of flying and diving and to test whether overall dynamic body acceleration (ODBA) is a reliable predictor of DEE in this abundant seabird. Average DEE for chick-rearing dovekies was 604±119 kJ/d across both sampling years. Despite recording lower stroke frequencies for diving than for flying (in line with allometric predictions for auks), dive costs were estimated to surpass flight costs in our sample of birds (flying: 7.24, diving: 9.37 X BMR). As expected, ODBA was not an effective predictor of DEE in this species. However, accelerometer-derived time budgets did accurately estimate DEE in dovekies. This work represents an empirical example of how the apparent energetic costs of buoyancy and thermoregulation limit the effectiveness of ODBA as the sole predictor of overall energy expenditure in small shallow-diving endotherms.","PeriodicalId":22458,"journal":{"name":"THE EGYPTIAN JOURNAL OF EXPERIMENTAL BIOLOGY","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90421606","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 7