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1.
Int J Mol Sci ; 23(3)2022 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-35163418

RESUMO

Damage to organs by trauma, infection, diseases, congenital defects, aging, and other injuries causes organ malfunction and is life-threatening under serious conditions. Some of the lower order vertebrates such as zebrafish, salamanders, and chicks possess superior organ regenerative capacity over mammals. The extracellular signal-regulated kinases 1 and 2 (ERK1/2), as key members of the mitogen-activated protein kinase (MAPK) family, are serine/threonine protein kinases that are phylogenetically conserved among vertebrate taxa. MAPK/ERK signaling is an irreplaceable player participating in diverse biological activities through phosphorylating a broad variety of substrates in the cytoplasm as well as inside the nucleus. Current evidence supports a central role of the MAPK/ERK pathway during organ regeneration processes. MAPK/ERK signaling is rapidly excited in response to injury stimuli and coordinates essential pro-regenerative cellular events including cell survival, cell fate turnover, migration, proliferation, growth, and transcriptional and translational activities. In this literature review, we recapitulated the multifaceted MAPK/ERK signaling regulations, its dynamic spatio-temporal activities, and the profound roles during multiple organ regeneration, including appendages, heart, liver, eye, and peripheral/central nervous system, illuminating the possibility of MAPK/ERK signaling as a critical mechanism underlying the vastly differential regenerative capacities among vertebrate species, as well as its potential applications in tissue engineering and regenerative medicine.


Assuntos
MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Sistema de Sinalização das MAP Quinases , Organogênese/fisiologia , Regeneração/fisiologia , Vertebrados/fisiologia , Animais , MAP Quinases Reguladas por Sinal Extracelular/química , Humanos , Modelos Biológicos
2.
Biol Rev Camb Philos Soc ; 97(2): 766-801, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34894040

RESUMO

The whole-body (tachymetabolic) endothermy seen in modern birds and mammals is long held to have evolved independently in each group, a reasonable assumption when it was believed that its earliest appearances in birds and mammals arose many millions of years apart. That assumption is consistent with current acceptance that the non-shivering thermogenesis (NST) component of regulatory body heat originates differently in each group: from skeletal muscle in birds and from brown adipose tissue (BAT) in mammals. However, BAT is absent in monotremes, marsupials, and many eutherians, all whole-body endotherms. Indeed, recent research implies that BAT-driven NST originated more recently and that the biochemical processes driving muscle NST in birds, many modern mammals and the ancestors of both may be similar, deriving from controlled 'slippage' of Ca2+ from the sarcoplasmic reticulum Ca2+ -ATPase (SERCA) in skeletal muscle, similar to a process seen in some fishes. This similarity prompted our realisation that the capacity for whole-body endothermy could even have pre-dated the divergence of Amniota into Synapsida and Sauropsida, leading us to hypothesise the homology of whole-body endothermy in birds and mammals, in contrast to the current assumption of their independent (convergent) evolution. To explore the extent of similarity between muscle NST in mammals and birds we undertook a detailed review of these processes and their control in each group. We found considerable but not complete similarity between them: in extant mammals the 'slippage' is controlled by the protein sarcolipin (SLN), in birds the SLN is slightly different structurally and its role in NST is not yet proved. However, considering the multi-millions of years since the separation of synapsids and diapsids, we consider that the similarity between NST production in birds and mammals is consistent with their whole-body endothermy being homologous. If so, we should expect to find evidence for it much earlier and more widespread among extinct amniotes than is currently recognised. Accordingly, we conducted an extensive survey of the palaeontological literature using established proxies. Fossil bone histology reveals evidence of sustained rapid growth rates indicating tachymetabolism. Large body size and erect stature indicate high systemic arterial blood pressures and four-chambered hearts, characteristic of tachymetabolism. Large nutrient foramina in long bones are indicative of high bone perfusion for rapid somatic growth and for repair of microfractures caused by intense locomotion. Obligate bipedality appeared early and only in whole-body endotherms. Isotopic profiles of fossil material indicate endothermic levels of body temperature. These proxies led us to compelling evidence for the widespread occurrence of whole-body endothermy among numerous extinct synapsids and sauropsids, and very early in each clade's family tree. These results are consistent with and support our hypothesis that tachymetabolic endothermy is plesiomorphic in Amniota. A hypothetical structure for the heart of the earliest endothermic amniotes is proposed. We conclude that there is strong evidence for whole-body endothermy being ancient and widespread among amniotes and that the similarity of biochemical processes driving muscle NST in extant birds and mammals strengthens the case for its plesiomorphy.


Assuntos
Aves , Mamíferos , Tecido Adiposo Marrom/fisiologia , Animais , Evolução Biológica , Aves/fisiologia , Mamíferos/fisiologia , Termogênese/fisiologia , Vertebrados/fisiologia
3.
Artigo em Inglês | MEDLINE | ID: mdl-34571153

RESUMO

Human-induced climate change is occurring rapidly. Ectothermic organisms are particularly vulnerable to these temperature changes due to their reliance on environmental temperature. The extent of ectothermic thermal adaptation and plasticity in the literature is well documented; however, the role of oxidative stress in these processes needs more attention. Oxidative stress occurs when reactive oxygen species, generated mainly through aerobic respiration, overwhelm antioxidant defences and damage crucial biomolecules. The effects of oxidative damage include the alteration of life-history traits and reductions in whole-organism fitness. Here we review the literature addressing experimental temperature effects on oxidative stress in vertebrate ectotherms. Acute and acclimation temperature treatments produce distinctly different results and highlight the role of phylogeny and thermal adaptation in shaping oxidative stress responses. Acute treatments on organisms adapted to stable environments generally produced significant oxidative stress responses, whilst organisms adapted to variable conditions exhibited capacity to cope with temperature changes and mitigate oxidative stress. In acclimation treatments, the temperature treatments higher than optimal temperatures tended to produce significantly less oxidative stress than lower temperatures in reptiles, whilst in some eurythermal fish species, no oxidative stress response was observed. These results highlight the importance of phylogeny and adaptation to past environmental conditions for temperature-dependent oxidative stress responses. We conclude with recommendations on experimental procedures to investigate these phenomena with reference to thermal plasticity, adaptation and biogeographic variation that provide the most significant benefits to adaptable populations. These results have potential conservation ramifications as they may shed light on the physiological effects of temperature alterations in some vertebrate ectotherms.


Assuntos
Mudança Climática , Estresse Oxidativo , Vertebrados/fisiologia , Aclimatação/fisiologia , Animais , Biomarcadores/metabolismo , Peixes/fisiologia , Humanos , Modelos Biológicos , Espécies Reativas de Oxigênio/metabolismo , Répteis/fisiologia , Temperatura
4.
Physiol Rev ; 102(1): 61-154, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34254835

RESUMO

The biological olfactory system is the sensory system responsible for the detection of the chemical composition of the environment. Several attempts to mimic biological olfactory systems have led to various artificial olfactory systems using different technical approaches. Here we provide a parallel description of biological olfactory systems and their technical counterparts. We start with a presentation of the input to the systems, the stimuli, and treat the interface between the external world and the environment where receptor neurons or artificial chemosensors reside. We then delineate the functions of receptor neurons and chemosensors as well as their overall input-output (I/O) relationships. Up to this point, our accounts of the systems go along similar lines. The next processing steps differ considerably: whereas in biology the processing step following the receptor neurons is the "integration" and "processing" of receptor neuron outputs in the olfactory bulb, this step has various realizations in electronic noses. For a long period of time, the signal processing stages beyond the olfactory bulb, i.e., the higher olfactory centers, were little studied. Only recently has there been a marked growth of studies tackling the information processing in these centers. In electronic noses, a third stage of processing has virtually never been considered. In this review, we provide an up-to-date overview of the current knowledge of both fields and, for the first time, attempt to tie them together. We hope it will be a breeding ground for better information, communication, and data exchange between very related but so far little-connected fields.


Assuntos
Bulbo Olfatório/fisiologia , Neurônios Receptores Olfatórios/fisiologia , Células Receptoras Sensoriais/fisiologia , Olfato/fisiologia , Animais , Humanos , Odorantes , Vertebrados/fisiologia
5.
Philos Trans R Soc Lond B Biol Sci ; 377(1844): 20200521, 2022 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-34957847

RESUMO

The primary driver of the evolution of the vertebrate nervous system has been the necessity to move, along with the requirement of controlling the plethora of motor behavioural repertoires seen among the vast and diverse vertebrate species. Understanding the neural basis of motor control through the perspective of evolution, mandates thorough examinations of the nervous systems of species in critical phylogenetic positions. We present here, a broad review of studies on the neural motor infrastructure of the lamprey, a basal and ancient vertebrate, which enjoys a unique phylogenetic position as being an extant representative of the earliest group of vertebrates. From the central pattern generators in the spinal cord to the microcircuits of the pallial cortex, work on the lamprey brain over the years, has provided detailed insights into the basic organization (a bauplan) of the ancestral vertebrate brain, and narrates a compelling account of common ancestry of fundamental aspects of the neural bases for motion control, maintained through half a billion years of vertebrate evolution. This article is part of the theme issue 'Systems neuroscience through the lens of evolutionary theory'.


Assuntos
Lampreias , Vertebrados , Animais , Evolução Biológica , Lampreias/fisiologia , Filogenia , Medula Espinal/fisiologia , Vertebrados/fisiologia
6.
Science ; 374(6575): eabf5787, 2021 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-34941418

RESUMO

Body sizes of marine amniotes span six orders of magnitude, yet the factors that governed the evolution of this diversity are largely unknown. High primary production of modern oceans is considered a prerequisite for the emergence of cetacean giants, but that condition cannot explain gigantism in Triassic ichthyosaurs. We describe the new giant ichthyosaur Cymbospondylus youngorum sp. nov. with a 2-meter-long skull from the Middle Triassic Fossil Hill Fauna of Nevada, USA, underscoring rapid size evolution despite the absence of many modern primary producers. Surprisingly, the Fossil Hill Fauna rivaled the composition of modern marine mammal faunas in terms of size range, and energy-flux models suggest that Middle Triassic marine food webs were able to support several large-bodied ichthyosaurs at high trophic levels, shortly after ichthyosaur origins.


Assuntos
Evolução Biológica , Tamanho Corporal , Cetáceos/anatomia & histologia , Fósseis , Répteis/anatomia & histologia , Animais , Organismos Aquáticos , Cetáceos/fisiologia , Simulação por Computador , Dieta , Ecossistema , Cadeia Alimentar , Filogenia , Répteis/classificação , Répteis/fisiologia , Crânio/anatomia & histologia , Vertebrados/anatomia & histologia , Vertebrados/fisiologia
7.
Nat Commun ; 12(1): 5442, 2021 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-34521846

RESUMO

Reversible switching of the bacterial flagellar motor between clockwise (CW) and counterclockwise (CCW) rotation is necessary for chemotaxis, which enables cells to swim towards favorable chemical habitats. Increase in the viscous resistance to the rotation of the motor (mechanical load) inhibits switching. However, cells must maintain homeostasis in switching to navigate within environments of different viscosities. The mechanism by which the cell maintains optimal chemotactic function under varying loads is not understood. Here, we show that the flagellar motor allosterically controls the binding affinity of the chemotaxis response regulator, CheY-P, to the flagellar switch complex by modulating the mechanical forces acting on the rotor. Mechanosensitive CheY-P binding compensates for the load-induced loss of switching by precisely adapting the switch response to a mechanical stimulus. The interplay between mechanical forces and CheY-P binding tunes the chemotactic function to match the load. This adaptive response of the chemotaxis output to mechanical stimuli resembles the proprioceptive feedback in the neuromuscular systems of insects and vertebrates.


Assuntos
Proteínas de Bactérias/metabolismo , Escherichia coli/metabolismo , Flagelos/metabolismo , Proteínas Quimiotáticas Aceptoras de Metil/metabolismo , Regulação Alostérica , Animais , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Mimetismo Biológico , Fenômenos Biomecânicos , Quimiotaxia/genética , Escherichia coli/genética , Escherichia coli/ultraestrutura , Proteínas de Escherichia coli , Retroalimentação Sensorial/fisiologia , Flagelos/genética , Flagelos/ultraestrutura , Expressão Gênica , Insetos/fisiologia , Proteínas Quimiotáticas Aceptoras de Metil/química , Proteínas Quimiotáticas Aceptoras de Metil/genética , Pinças Ópticas , Ligação Proteica , Vertebrados/fisiologia , Viscosidade
8.
Horm Behav ; 136: 105059, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34508875

RESUMO

Unpredictable environmental changes displace individuals from homeostasis and elicit a stress response. In vertebrates, the stress response is mediated mainly by glucocorticoids (GCs) which initiate physiological changes while minimizing allostatic overload. Individuals and species vary consistently in baseline and stress-induced GC levels and the speed with which GC levels can be upregulated or downregulated, but the extent to which variation in hormone regulation influences baseline and stress-induced GC levels is unclear. Using mathematical modeling, we tested how GC regulation rate, frequencies and durations of acute stressors, fitness functions, and allostatic overload affect GC levels during control and acute stress periods. As GC regulation rate slows, baseline and acute stress-induced GC levels become more similar. When the speed of up- and downregulation decreased, hormone levels became more linked to anticipated future conditions to avoid fitness costs of mismatching a new environmental state. More frequent acute stressors caused baseline and acute stress-induced GC levels to converge. When fitness was more tightly linked to hormone levels during acute stress periods than during control states, the speed of upregulation influenced optimal hormone levels more than the downregulation rate. With allostatic overload costs included, predicted GC levels were lower and more dependent on the frequency of past acute stressors. Our results show the value of optimality modeling to study the hormonal response to stressors and suggest GC levels depend on past and anticipated future environmental states as well as individual differences in hormone regulation.


Assuntos
Alostase , Glucocorticoides , Animais , Homeostase , Humanos , Vertebrados/fisiologia
9.
Adv Sci (Weinh) ; 8(20): e2102536, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34449132

RESUMO

Evolution has decided to gift an articular structure to vertebrates, but not to invertebrates, owing to their distinct survival strategies. An articular structure permits kinematic motion in creatures. However, it is inappropriate for creatures whose survival strategy depends on the high deformability of their body. Accordingly, a material in which the presence of the articular structure can be altered, allowing the use of two contradictory strategies, will be advantageous in diverse dynamic applications. Herein, spatial micro-water molecule manipulation, termed engineering on variable occupation of water (EVO), that is used to realize a material with dual mechanical modes that exhibit extreme differences in stiffness is introduced. A transparent and homogeneous soft material (110 kPa) reversibly converts to an opaque material embodying a mechanical gradient (ranging from 1 GPa to 1 MPa) by on-demand switching. Intensive theoretical analysis of EVO yields the design of spatial transformation scheme. The EVO gel accomplishes kinematic motion planning and shows great promise for multimodal kinematics. This approach paves the way for the development and application of smart functional materials.


Assuntos
Evolução Biológica , Amplitude de Movimento Articular/fisiologia , Vertebrados/fisiologia , Água/metabolismo , Animais , Fenômenos Biomecânicos , Movimento (Física)
10.
Philos Trans R Soc Lond B Biol Sci ; 376(1835): 20200335, 2021 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-34420380

RESUMO

Rhythmic behaviour is ubiquitous in both human and non-human animals, but it is unclear whether the cognitive mechanisms underlying the specific rhythmic behaviours observed in different species are related. Laboratory experiments combined with highly controlled stimuli and tasks can be very effective in probing the cognitive architecture underlying rhythmic abilities. Rhythmic abilities have been examined in the laboratory with explicit and implicit perception tasks, and with production tasks, such as sensorimotor synchronization, with stimuli ranging from isochronous sequences of artificial sounds to human music. Here, we provide an overview of experimental findings on rhythmic abilities in human and non-human animals, while critically considering the wide variety of paradigms used. We identify several gaps in what is known about rhythmic abilities. Many bird species have been tested on rhythm perception, but research on rhythm production abilities in the same birds is lacking. By contrast, research in mammals has primarily focused on rhythm production rather than perception. Many experiments also do not differentiate between possible components of rhythmic abilities, such as processing of single temporal intervals, rhythmic patterns, a regular beat or hierarchical metrical structures. For future research, we suggest a careful choice of paradigm to aid cross-species comparisons, and a critical consideration of the multifaceted abilities that underlie rhythmic behaviour. This article is part of the theme issue 'Synchrony and rhythm interaction: from the brain to behavioural ecology'.


Assuntos
Percepção Auditiva , Etologia/métodos , Invertebrados/fisiologia , Música , Periodicidade , Som , Vertebrados/fisiologia , Estimulação Acústica , Animais , Humanos , Percepção do Tempo
11.
Philos Trans R Soc Lond B Biol Sci ; 376(1835): 20200336, 2021 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-34420382

RESUMO

In this perspective paper, we focus on the study of synchronization abilities across the animal kingdom. We propose an ecological approach to studying nonhuman animal synchronization that begins from observations about when, how and why an animal might synchronize spontaneously with natural environmental rhythms. We discuss what we consider to be the most important, but thus far largely understudied, temporal, physical, perceptual and motivational constraints that must be taken into account when designing experiments to test synchronization in nonhuman animals. First and foremost, different species are likely to be sensitive to and therefore capable of synchronizing at different timescales. We also argue that it is fruitful to consider the latent flexibility of animal synchronization. Finally, we discuss the importance of an animal's motivational state for showcasing synchronization abilities. We demonstrate that the likelihood that an animal can successfully synchronize with an environmental rhythm is context-dependent and suggest that the list of species capable of synchronization is likely to grow when tested with ecologically honest, species-tuned experiments. This article is part of the theme issue 'Synchrony and rhythm interaction: from the brain to behavioural ecology'.


Assuntos
Etologia/métodos , Invertebrados/fisiologia , Vertebrados/fisiologia , Animais , Comportamento Animal , Ecologia/métodos , Periodicidade
12.
Curr Opin Neurobiol ; 71: 11-18, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34450468

RESUMO

A comparison of the vertebrate motor systems of the oldest group of now living vertebrates (lamprey) with that of mammals shows that there are striking similarities not only in the basic organization but also with regard to synaptic properties, transmitters and neuronal properties. The lamprey dorsal pallium (cortex) has a motor, a visual and a somatosensory area, and the basal ganglia, including the dopamine system, are organized in a virtually identical way in the lamprey and rodents. This also applies to the midbrain, brainstem and spinal cord. However, during evolution additional capabilities such as systems for the control of foreleg/arms, hands and fingers have evolved. The findings suggest that when the evolutionary lineages of mammals and lamprey became separate around 500 million years ago, the blueprint of the vertebrate motor system had already evolved.


Assuntos
Evolução Biológica , Vertebrados , Animais , Lampreias/fisiologia , Mamíferos , Prosencéfalo , Medula Espinal , Vertebrados/fisiologia
13.
Development ; 148(15)2021 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-34323269

RESUMO

During early development, the hindbrain is sub-divided into rhombomeres that underlie the organisation of neurons and adjacent craniofacial tissues. A gene regulatory network of signals and transcription factors establish and pattern segments with a distinct anteroposterior identity. Initially, the borders of segmental gene expression are imprecise, but then become sharply defined, and specialised boundary cells form. In this Review, we summarise key aspects of the conserved regulatory cascade that underlies the formation of hindbrain segments. We describe how the pattern is sharpened and stabilised through the dynamic regulation of cell identity, acting in parallel with cell segregation. Finally, we discuss evidence that boundary cells have roles in local patterning, and act as a site of neurogenesis within the hindbrain.


Assuntos
Padronização Corporal/fisiologia , Rombencéfalo/crescimento & desenvolvimento , Rombencéfalo/fisiologia , Vertebrados/crescimento & desenvolvimento , Vertebrados/fisiologia , Animais , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Redes Reguladoras de Genes/fisiologia , Humanos
15.
Philos Trans R Soc Lond B Biol Sci ; 376(1830): 20200210, 2021 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-34121463

RESUMO

By describing where animals go, biologging technologies (i.e. animal attached logging of biological variables with small electronic devices) have been used to document the remarkable athletic feats of wild animals since the 1940s. The rapid development and miniaturization of physiologging (i.e. logging of physiological variables such as heart rate, blood oxygen content, lactate, breathing frequency and tidal volume on devices attached to animals) technologies in recent times (e.g. devices that weigh less than 2 g mass that can measure electrical biopotentials for days to weeks) has provided astonishing insights into the physiology of free-living animals to document how and why wild animals undertake these extreme feats. Now, physiologging, which was traditionally hindered by technological limitations, device size, ethics and logistics, is poised to benefit enormously from the on-going developments in biomedical and sports wearables technologies. Such technologies are already improving animal welfare and yield in agriculture and aquaculture, but may also reveal future pathways for therapeutic interventions in human health by shedding light on the physiological mechanisms with which free-living animals undertake some of the most extreme and impressive performances on earth. This article is part of the theme issue 'Measuring physiology in free-living animals (Part I)'.


Assuntos
Fisiologia/métodos , Vertebrados/fisiologia , Animais , Metabolismo Energético/fisiologia , Frequência Cardíaca/fisiologia , Fisiologia/instrumentação
16.
Curr Biol ; 31(11): R741-R762, 2021 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-34102128

RESUMO

The superior colliculus, or tectum in the case of non-mammalian vertebrates, is a part of the brain that registers events in the surrounding space, often through vision and hearing, but also through electrosensation, infrared detection, and other sensory modalities in diverse vertebrate lineages. This information is used to form maps of the surrounding space and the positions of different salient stimuli in relation to the individual. The sensory maps are arranged in layers with visual input in the uppermost layer, other senses in deeper positions, and a spatially aligned motor map in the deepest layer. Here, we will review the organization and intrinsic function of the tectum/superior colliculus and the information that is processed within tectal circuits. We will also discuss tectal/superior colliculus outputs that are conveyed directly to downstream motor circuits or via the thalamus to cortical areas to control various aspects of behavior. The tectum/superior colliculus is evolutionarily conserved among all vertebrates, but tailored to the sensory specialties of each lineage, and its roles have shifted with the emergence of the cerebral cortex in mammals. We will illustrate both the conserved and divergent properties of the tectum/superior colliculus through vertebrate evolution by comparing tectal processing in lampreys belonging to the oldest group of extant vertebrates, larval zebrafish, rodents, and other vertebrates including primates.


Assuntos
Córtex Cerebral/fisiologia , Processamento Espacial/fisiologia , Colículos Superiores/fisiologia , Vertebrados/fisiologia , Vias Visuais , Animais , Humanos , Lampreias/fisiologia , Primatas/fisiologia , Roedores/fisiologia , Peixe-Zebra/fisiologia
17.
Cells ; 10(6)2021 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-34067375

RESUMO

(1) Background: High-tension glaucoma damages the peripheral vision dominated by rods. How mechanosensitive channels (MSCs) in the outer retina mediate pressure responses is unclear. (2) Methods: Immunocytochemistry, patch clamp, and channel fluorescence were used to study MSCs in salamander photoreceptors. (3) Results: Immunoreactivity of transient receptor potential channel vanilloid 4 (TRPV4) was revealed in the outer plexiform layer, K+ channel TRAAK in the photoreceptor outer segment (OS), and TRPV2 in some rod OS disks. Pressure on the rod inner segment evoked sustained currents of three components: (A) the inward current at <-50 mV (Ipi), sensitive to Co2+; (B) leak outward current at ≥-80 mV (Ipo), sensitive to intracellular Cs+ and ruthenium red; and (C) cation current reversed at ~10 mV (Ipc). Hypotonicity induced slow currents like Ipc. Environmental pressure and light increased the FM 1-43-identified open MSCs in the OS membrane, while pressure on the OS with internal Cs+ closed a Ca2+-dependent current reversed at ~0 mV. Rod photocurrents were thermosensitive and affected by MSC blockers. (4) Conclusions: Rods possess depolarizing (TRPV) and hyperpolarizing (K+) MSCs, which mediate mutually compensating currents between -50 mV and 10 mV, serve as an electrical cushion to minimize the impact of ocular mechanical stress.


Assuntos
Potenciais da Membrana/fisiologia , Células Fotorreceptoras/fisiologia , Retina/fisiologia , Visão Ocular/fisiologia , Animais , Cálcio/metabolismo , Cálcio/farmacologia , Potenciais da Membrana/efeitos dos fármacos , Retina/efeitos dos fármacos , Neurônios Retinianos/efeitos dos fármacos , Neurônios Retinianos/fisiologia , Vertebrados/fisiologia , Visão Ocular/efeitos dos fármacos
18.
PLoS One ; 16(6): e0252049, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34086677

RESUMO

Females of many vertebrate species have the capacity to store sperm within their reproductive tracts for prolonged periods of time. Termed long-term sperm storage, this phenomenon has many important physiological, ecological, and evolutionary implications, particularly to the study of mating systems, including male reproductive success and post-copulatory sexual selection. Reptiles appear particularly predisposed to long-term sperm storage, with records in most major lineages, with a strong emphasis on turtles and squamates (lizards, snakes, but not the amphisbaenians). Because facultative parthenogenesis is a competing hypothesis to explain the production of offspring after prolonged separation from males, the identification of paternal alleles through genetic analysis is essential. However, few studies in snakes have undertaken this. Here, we report on a wild-collected female Western Diamond-backed Rattlesnake, Crotalus atrox, maintained in isolation from the time of capture in September 1999, that produced two healthy litters approximately one and six years post capture. Genetic analysis of the 2005 litter, identified paternal contribution in all offspring, thus rejecting facultative parthenogenesis. We conclude that the duration of long-term sperm storage was approximately 6 years (71 months), making this the longest period over which a female vertebrate has been shown to store sperm that resulted in the production of healthy offspring.


Assuntos
Espermatozoides/fisiologia , Vertebrados/fisiologia , Animais , Evolução Biológica , Feminino , Genótipo , Masculino , Repetições de Microssatélites/fisiologia , Reprodução/fisiologia , Comportamento Sexual Animal/fisiologia
19.
Philos Trans R Soc Lond B Biol Sci ; 376(1831): 20200479, 2021 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-34176323

RESUMO

How individuals interact with their environment and respond to changes is a key area of research in evolutionary biology. A physiological parameter that provides an instant proxy for the activation of the automatic nervous system, and can be measured relatively easily, is modulation of heart rate. Over the past four decades, heart rate has been used to assess emotional arousal in non-human animals in a variety of contexts, including social behaviour, animal cognition, animal welfare and animal personality. In this review, I summarize how measuring heart rate has provided new insights into how social animals cope with challenges in their environment. I assess the advantages and limitations of different technologies used to measure heart rate in this context, including wearable heart rate belts and implantable transmitters, and provide an overview of prospective research avenues using established and new technologies, with a special focus on implications for applied research on animal welfare. This article is part of the theme issue 'Measuring physiology in free-living animals (Part II)'.


Assuntos
Bem-Estar do Animal , Nível de Alerta/fisiologia , Emoções/fisiologia , Frequência Cardíaca/fisiologia , Vertebrados/fisiologia , Animais , Comportamento Social
20.
Philos Trans R Soc Lond B Biol Sci ; 376(1831): 20200227, 2021 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-34176325

RESUMO

Recent advances in tagging and biologging technology have yielded unprecedented insights into wild animal physiology. However, time-series data from such wild tracking studies present numerous analytical challenges owing to their unique nature, often exhibiting strong autocorrelation within and among samples, low samples sizes and complicated random effect structures. Gleaning robust quantitative estimates from these physiological data, and, therefore, accurate insights into the life histories of the animals they pertain to, requires careful and thoughtful application of existing statistical tools. Using a combination of both simulated and real datasets, I highlight the key pitfalls associated with analysing physiological data from wild monitoring studies, and investigate issues of optimal study design, statistical power, and model precision and accuracy. I also recommend best practice approaches for dealing with their inherent limitations. This work will provide a concise, accessible roadmap for researchers looking to maximize the yield of information from complex and hard-won biologging datasets. This article is part of the theme issue 'Measuring physiology in free-living animals (Part II)'.


Assuntos
Fisiologia/instrumentação , Vertebrados/fisiologia , Animais , Fatores de Tempo
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