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Birk MA, Liscovitch-Brauer N, Dominguez MJ, McNeme S, Yue Y, Hoff JD, Twersky I, Verhey KJ, Sutton RB, Eisenberg E, Rosenthal JJC. Temperature-dependent RNA editing in octopus extensively recodes the neural proteome. Cell 2023; 186:2544-2555.e13. [PMID: 37295402 PMCID: PMC10445230 DOI: 10.1016/j.cell.2023.05.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 04/24/2023] [Accepted: 05/04/2023] [Indexed: 06/12/2023]
Abstract
In poikilotherms, temperature changes challenge the integration of physiological function. Within the complex nervous systems of the behaviorally sophisticated coleoid cephalopods, these problems are substantial. RNA editing by adenosine deamination is a well-positioned mechanism for environmental acclimation. We report that the neural proteome of Octopus bimaculoides undergoes massive reconfigurations via RNA editing following a temperature challenge. Over 13,000 codons are affected, and many alter proteins that are vital for neural processes. For two highly temperature-sensitive examples, recoding tunes protein function. For synaptotagmin, a key component of Ca2+-dependent neurotransmitter release, crystal structures and supporting experiments show that editing alters Ca2+ binding. For kinesin-1, a motor protein driving axonal transport, editing regulates transport velocity down microtubules. Seasonal sampling of wild-caught specimens indicates that temperature-dependent editing occurs in the field as well. These data show that A-to-I editing tunes neurophysiological function in response to temperature in octopus and most likely other coleoids.
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Affiliation(s)
- Matthew A Birk
- Bell Center, Marine Biological Laboratory, Woods Hole, MA 02543, USA; Department of Biology, Saint Francis University, Loretto, PA 15940, USA
| | | | - Matthew J Dominguez
- Department of Cell Physiology and Molecular Biophysics, Texas Tech University Health Sciences Center, Lubbock, TX 79410, USA
| | - Sean McNeme
- Department of Biochemistry and Molecular Biology, The University of Texas Medical Branch, Galveston, TX 77550, USA
| | - Yang Yue
- Department of Cell & Developmental Biology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - J Damon Hoff
- Department of Biophysics, University of Michigan, Ann Arbor, MI 48109, USA
| | - Itamar Twersky
- The Nano Center, The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, Israel
| | - Kristen J Verhey
- Department of Cell & Developmental Biology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - R Bryan Sutton
- Department of Cell Physiology and Molecular Biophysics, Texas Tech University Health Sciences Center, Lubbock, TX 79410, USA
| | - Eli Eisenberg
- School of Physics and Astronomy, Tel Aviv University, Tel Aviv 69978, Israel.
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2
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Pahlavan B, Buitrago N, Santamaria F. Macromolecular rate theory explains the temperature dependence of membrane conductance kinetics. Biophys J 2023; 122:522-532. [PMID: 36567527 PMCID: PMC9941726 DOI: 10.1016/j.bpj.2022.12.033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Revised: 10/19/2022] [Accepted: 12/23/2022] [Indexed: 12/25/2022] Open
Abstract
The factor Q10 is used in neuroscience to adjust reaction rates of voltage-activated membrane conductances to different temperatures and is widely assumed to be constant. By performing an analysis of published data of the reaction rates of sodium, potassium, and calcium membrane conductances, we demonstrate that 1) Q10 is temperature dependent, 2) this relationship is similar across conductances, and 3) there is a strong effect at low temperatures (<15°C). We show that macromolecular rate theory (MMRT) explains this temperature dependency. MMRT predicts the existence of optimal temperatures at which reaction rates decrease as temperature increases, a phenomenon that we also found in the published data sets. We tested the consequences of using MMRT-adjusted reaction rates in the Hodgkin-Huxley model of the squid's giant axon. The MMRT-adjusted model reproduces the temperature dependence of the rising and falling times of the action potential. Furthermore, the model also reproduces these properties for different squid species that live in different climates. In a second example, we compare spiking patterns of biophysical models based on human pyramidal neurons from the Allen Cell Types database at room and physiological temperatures. The original models, calibrated at 34°C, failed to generate realistic spikes at room temperature in more than half of the tested models, while the MMRT produces realistic spiking in all conditions. In another example, we show that using the MMRT correction in hippocampal pyramidal cell models results in 100% differences in voltage responses. Finally, we show that the shape of the Q10 function results in systematic errors in predicting reaction rates. We propose that the optimal temperature could be a thermodynamical barrier to avoid over excitation in neurons. While this study is centered on membrane conductances, our results have important consequences for all biochemical reactions involved in cell signaling.
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Affiliation(s)
- Bahram Pahlavan
- Department of Neuroscience, Developmental and Regenerative Biology, The University of Texas at San Antonio, San Antonio, Texas
| | - Nicolas Buitrago
- Department of Neuroscience, Developmental and Regenerative Biology, The University of Texas at San Antonio, San Antonio, Texas
| | - Fidel Santamaria
- Department of Neuroscience, Developmental and Regenerative Biology, The University of Texas at San Antonio, San Antonio, Texas.
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3
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Himmel NJ, Letcher JM, Sakurai A, Gray TR, Benson MN, Donaldson KJ, Cox DN. Identification of a neural basis for cold acclimation in Drosophila larvae. iScience 2021; 24:102657. [PMID: 34151240 PMCID: PMC8192725 DOI: 10.1016/j.isci.2021.102657] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Revised: 04/05/2021] [Accepted: 05/25/2021] [Indexed: 11/29/2022] Open
Abstract
Low temperatures can be fatal to insects, but many species have evolved the ability to cold acclimate, thereby increasing their cold tolerance. It has been previously shown that Drosophila melanogaster larvae perform cold-evoked behaviors under the control of noxious cold-sensing neurons (nociceptors), but it is unknown how the nervous system might participate in cold tolerance. Herein, we describe cold-nociceptive behavior among 11 drosophilid species; we find that the predominant cold-evoked larval response is a head-to-tail contraction behavior, which is likely inherited from a common ancestor, but is unlikely to be protective. We therefore tested the hypothesis that cold nociception functions to protect larvae by triggering cold acclimation. We found that Drosophila melanogaster Class III nociceptors are sensitized by and critical to cold acclimation and that cold acclimation can be optogenetically evoked, sans cold. Collectively, these findings demonstrate that cold nociception constitutes a peripheral neural basis for Drosophila larval cold acclimation.
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Affiliation(s)
- Nathaniel J Himmel
- Neuroscience Institute, Georgia State University, Atlanta, GA 30303, USA
| | - Jamin M Letcher
- Neuroscience Institute, Georgia State University, Atlanta, GA 30303, USA
| | - Akira Sakurai
- Neuroscience Institute, Georgia State University, Atlanta, GA 30303, USA
| | - Thomas R Gray
- Neuroscience Institute, Georgia State University, Atlanta, GA 30303, USA.,Department of Biology, Brandeis University, Waltham, MA 02453, USA
| | - Maggie N Benson
- Neuroscience Institute, Georgia State University, Atlanta, GA 30303, USA
| | - Kevin J Donaldson
- Neuroscience Institute, Georgia State University, Atlanta, GA 30303, USA
| | - Daniel N Cox
- Neuroscience Institute, Georgia State University, Atlanta, GA 30303, USA
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4
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Boroda AV, Kipryushina YO, Odintsova NA. The effects of cold stress on Mytilus species in the natural environment. Cell Stress Chaperones 2020; 25:821-832. [PMID: 32297161 PMCID: PMC7591686 DOI: 10.1007/s12192-020-01109-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 03/26/2020] [Accepted: 04/01/2020] [Indexed: 10/24/2022] Open
Abstract
Environmental stressors induce changes in marine mussels from molecular (e.g., neurotransmitter and chaperone concentration, and expression of immune- and heat-shock protein-related genes) to physiological (e.g., filtration and heart rates, the number of circulating hemocytes) levels. Temperature directly affects the biogeographic distribution of mussels. Chaperones might form an essential part of endogenous protective mechanisms for the adaptation of these animals to low temperatures in nature. Here, we review the available studies dealing with cold stress responses of Mytilidae family members in their natural environment.
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Affiliation(s)
- Andrey Victorovich Boroda
- National Scientific Center of Marine Biology of the Far Eastern Branch of the Russian Academy of Sciences, 17 Palchevsky St, Vladivostok, Primorsky Krai, 690041, Russia.
| | - Yulia Olegovna Kipryushina
- National Scientific Center of Marine Biology of the Far Eastern Branch of the Russian Academy of Sciences, 17 Palchevsky St, Vladivostok, Primorsky Krai, 690041, Russia
| | - Nelly Adolphovna Odintsova
- National Scientific Center of Marine Biology of the Far Eastern Branch of the Russian Academy of Sciences, 17 Palchevsky St, Vladivostok, Primorsky Krai, 690041, Russia
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5
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Youngblood JP, VandenBrooks JM, Babarinde O, Donnay ME, Elliott DB, Fredette-Roman J, Angilletta MJ. Oxygen supply limits the chronic heat tolerance of locusts during the first instar only. JOURNAL OF INSECT PHYSIOLOGY 2020; 127:104157. [PMID: 33098860 DOI: 10.1016/j.jinsphys.2020.104157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 10/15/2020] [Accepted: 10/16/2020] [Indexed: 06/11/2023]
Abstract
Although scientists know that overheating kills many organisms, they do not agree on the mechanism. According to one theory, referred to as oxygen- and capacity-limitation of thermal tolerance, overheating occurs when a warming organism's demand for oxygen exceeds its supply, reducing the organism's supply of ATP. This model predicts that an organism's heat tolerance should decrease under hypoxia, yet most terrestrial organisms tolerate the same amount of warming across a wide range of oxygen concentrations. This point is especially true for adult insects, who deliver oxygen through highly efficient respiratory systems. However, oxygen limitation at high temperatures may be more common during immature life stages, which have less developed respiratory systems. To test this hypothesis, we measured the effects of heat and hypoxia on the survival of South American locusts (Schistocerca cancellata) throughout development and during specific instars. We demonstrate that the heat tolerance of locusts depends on oxygen supply during the first instar but not during later instars. This finding provides further support for the idea that oxygen limitation of thermal tolerance depends on respiratory performance, especially during immature life stages.
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Affiliation(s)
- Jacob P Youngblood
- School of Life Sciences, Arizona State University, Tempe, AZ 85287, USA.
| | | | | | - Megan E Donnay
- School of Life Sciences, Arizona State University, Tempe, AZ 85287, USA
| | - Deanna B Elliott
- School of Life Sciences, Arizona State University, Tempe, AZ 85287, USA
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6
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Johnston MR, Herrick BM. Cocoon Heat Tolerance of Pheretimoid Earthworms Amynthas tokioensis and Amynthas agrestis. AMERICAN MIDLAND NATURALIST 2019. [DOI: 10.1674/0003-0031-181.2.299] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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7
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Bowler K. Heat death in poikilotherms: Is there a common cause? J Therm Biol 2018; 76:77-79. [DOI: 10.1016/j.jtherbio.2018.06.007] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Accepted: 06/15/2018] [Indexed: 11/25/2022]
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8
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Thermal acclimation and thyroxine treatment modify the electric organ discharge frequency in an electric fish, Apteronotus leptorhynchus. Physiol Behav 2015; 151:64-71. [PMID: 26143349 DOI: 10.1016/j.physbeh.2015.06.036] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Revised: 05/28/2015] [Accepted: 06/26/2015] [Indexed: 11/23/2022]
Abstract
In ectotherms, the rate of many neural processes is determined externally, by the influence of the thermal environment on body temperature, and internally, by hormones secreted from the thyroid gland. Through thermal acclimation, animals can buffer the influence of the thermal environment by adjusting their physiology to stabilize certain processes in the face of environmental temperature change. The electric organ discharge (EOD) used by weak electric fish for electrocommunication and electrolocation is highly temperature sensitive. In some temperate species that naturally experience large seasonal fluctuations in environmental temperature, the thermal sensitivity (Q10) of the EOD shifts after long-term temperature change. We examined thermal acclimation of EOD frequency in a tropical electric fish, Apteronotus leptorhynchus that naturally experiences much less temperature change. We transferred fish between thermal environments (25.3 and 27.8 °C) and measured EOD frequency and its thermal sensitivity (Q10) over 11 d. After 6d, fish exhibited thermal acclimation to both warming and cooling, adjusting the thermal dependence of EOD frequency to partially compensate for the small change (2.5 °C) in water temperature. In addition, we evaluated the thyroid influence on EOD frequency by treating fish with thyroxine or the anti-thyroid compound propylthiouricil (PTU) to stimulate or inhibit thyroid activity, respectively. Thyroxine treatment significantly increased EOD frequency, but PTU had no effect. Neither thyroxine nor PTU treatment influenced the thermal sensitivity (Q10) of EOD frequency during acute temperature change. Thus, the EOD of Apteronotus shows significant thermal acclimation and responds to elevated thyroxine.
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9
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Schulte PM. The effects of temperature on aerobic metabolism: towards a mechanistic understanding of the responses of ectotherms to a changing environment. J Exp Biol 2015; 218:1856-66. [DOI: 10.1242/jeb.118851] [Citation(s) in RCA: 387] [Impact Index Per Article: 43.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
ABSTRACT
Because of its profound effects on the rates of biological processes such as aerobic metabolism, environmental temperature plays an important role in shaping the distribution and abundance of species. As temperature increases, the rate of metabolism increases and then rapidly declines at higher temperatures – a response that can be described using a thermal performance curve (TPC). Although the shape of the TPC for aerobic metabolism is often attributed to the competing effects of thermodynamics, which can be described using the Arrhenius equation, and the effects of temperature on protein stability, this account represents an over-simplification of the factors acting even at the level of single proteins. In addition, it cannot adequately account for the effects of temperature on complex multistep processes, such as aerobic metabolism, that rely on mechanisms acting across multiple levels of biological organization. The purpose of this review is to explore our current understanding of the factors that shape the TPC for aerobic metabolism in response to acute changes in temperature, and to highlight areas where this understanding is weak or insufficient. Developing a more strongly grounded mechanistic model to account for the shape of the TPC for aerobic metabolism is crucial because these TPCs are the foundation of several recent attempts to predict the responses of species to climate change, including the metabolic theory of ecology and the hypothesis of oxygen and capacity-limited thermal tolerance.
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10
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Hyde D, Pearson T, Qari S, Bowler K. Adaptive considerations of temperature dependence of neuromuscular function in two species of summer- and winter-caught Crab (Carcinus maenas and Cancer pagurus). J Comp Physiol B 2015; 185:629-36. [PMID: 25994492 DOI: 10.1007/s00360-015-0912-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2014] [Revised: 05/06/2015] [Accepted: 05/13/2015] [Indexed: 11/29/2022]
Abstract
The aim of this study was to determine seasonal differences in the temperature dependence of neuromuscular parameters of the dactylopodite walking leg closer muscle in two species of freshly caught summer and winter decapod crabs. The relatively stenothermal Cancer pagurus (Cp) and eurythermal Carcinus maenas (Cm) muscle resting potential (RP) hyperpolarised significantly with increasing experimental temperature. The muscle RP in Cm was seasonally dependent at acute temperatures above 20 °C whereas in Cp no seasonal effect was observed. The latent period of the muscle excitatory junction potential (EJP) following tonic motor nerve stimulation was significantly longer in winter-caught crabs in both species, although the effect was significantly more marked in Cp than Cm. Summer-caught Cp had larger excitatory junction potentials (EJPs) than did winter-caught crabs, a seasonal effect not seen in Cm. In contrast, marked seasonal differences were found in the EJP decay time constant in Cm having significantly longer time constants in winter-caught crabs, where no seasonal difference was found in Cp. These results suggest that different seasonal effects of neuromuscular parameters between Cm and Cp may reflect different strategies of response to their different seasonal temperature environments.
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Affiliation(s)
- D Hyde
- Department of Biological and Biomedical Sciences, University of Durham, South Road, Durham, DH1 3LE, UK,
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11
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Temperature and neuronal circuit function: compensation, tuning and tolerance. Curr Opin Neurobiol 2012; 22:724-34. [DOI: 10.1016/j.conb.2012.01.008] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2012] [Revised: 01/18/2012] [Accepted: 01/19/2012] [Indexed: 01/24/2023]
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12
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Hyde D, Qari S, Hopkin R, Bowler K. Thermal acclimation, heat shock and photoperiod: Do these factors interplay in the adaptive responses of crab neuromuscular systems to temperature? J Therm Biol 2012. [DOI: 10.1016/j.jtherbio.2011.12.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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13
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14
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Moffett S, Wachtel H. Correlations between temperature effects on behavior inaplysiaand firing patterns of identified neurons. ACTA ACUST UNITED AC 2009. [DOI: 10.1080/10236247609386942] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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15
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Minimal levels of cold-adaptation in postsynaptic currents of a subantarctic teleost, Notothenia rossii (Perciformes: Notothenioidei: Nototheniidae). Polar Biol 2007. [DOI: 10.1007/s00300-006-0239-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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16
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. OMA, . MB, . RA. Age and Heat Stress Related Changes in Monoamine Contents and Cholinesterase Activity in Some Central Nervous System Regions of Albino Rat Newborns. ACTA ACUST UNITED AC 2007. [DOI: 10.3923/ijzr.2007.65.76] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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17
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Nedeljković M, Kartelija G, Radenović L. Effects of cooling on the response of the snail bursting neuron to acetylcholine. Ann N Y Acad Sci 2005; 1048:352-4. [PMID: 16154950 DOI: 10.1196/annals.1342.036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The Br-type neuron of the snail Helix pomatia, involved in neuronal regulation of various homeostatic and adaptive mechanisms, represents an interesting model for studying effects of temperature change on neuronal activity of poikilotherms. Acetylcholine induces a transient, inward dose-dependent current in the identified Br neuron. In the work presented, we analyzed the effects of cooling on the acetylcholine-induced inward current. The amplitude of acetylcholine-induced inward current was markedly decreased after cooling, and the speed of the decay of acetylcholine response was decreased.
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18
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Ahmed RG. Heat stress induced histopathology and pathophysiology of the central nervous system. Int J Dev Neurosci 2005; 23:549-57. [PMID: 16011888 DOI: 10.1016/j.ijdevneu.2005.05.005] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2005] [Revised: 03/07/2005] [Accepted: 03/11/2005] [Indexed: 11/30/2022] Open
Abstract
The number of reports on the effects of heat stress is still increasing on account of the temperature is one of the most encountered stressful factors on the different biological systems. Because the heat stress (HS) considered a model of thermal injury to the central nervous system (CNS), the purpose of this review was to assess the histopathological changes of HS on CNS. Also, this review emphasized that the heat stress may retard partially the degree of the postnatal neurogenesis and growth of CNS. Taken together, owing to one of the most important functions of heat shock protein is to protect the organisms from the deleterious effects of temperature, thus, it can be hypothesized that the formation of heat shock proteins may be related to the deleterious effect of HS. On the other hands, the alterations of neurotransmitters in the central nervous system might be involved in the physiological and biochemical responses that occur during heat stress. The hypothalamic monoaminergic systems play an important role in the thermoregulation through regulate the heat production and heat dissipation. In addition, the disturbance in the biochemical variables due to the high temperature may be the cause of the histopathological changes and the partial retardation in CNS and the reverse is true. Thus, further studies need to be done to emphasize this concept.
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Affiliation(s)
- R G Ahmed
- Department of Zoology, Faculty of Science, Cairo University, Beni-Suef, Branch, Beni-Suef, Egypt.
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20
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Haverinen J, Vornanen M. Temperature acclimation modifies Na+ current in fish cardiac myocytes. ACTA ACUST UNITED AC 2004; 207:2823-33. [PMID: 15235011 DOI: 10.1242/jeb.01103] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The present study was designed to test the hypothesis that temperature acclimation modifies sarcolemmal Na+ current (INa) of the fish cardiac myocytes differently depending on the animal's lifestyle in the cold. Two eurythermal fish species with different physiological strategies for surviving in the cold, a cold-dormant crucian carp (Carassius carassius L.) and a cold-active rainbow trout (Oncorhynchus mykiss), were used in acclimation experiments. The INa of carp and trout were also compared with INa of a cold stenothermal burbot (Lota lota). In accordance with the hypothesis, cold-acclimation decreased the density of INa in crucian carp and increased it in rainbow trout, suggesting depression of impulse conduction in cold-acclimated carp and positive compensation of impulse propagation in cold-acclimated trout. The steady-state activation curve of trout INa was shifted by 6 mV to more negative voltages by cold acclimation, which probably lowers the stimulus threshold for action potentials and further improves cardiac excitability in the cold. In burbot myocytes, the INa density was high and the position of the steady-state activation curve on the voltage axis was even more negative than in trout or carp myocytes, suggesting that the burbot INa is adapted to maintain high excitability and conductivity in the cold. The INa of the burbot heart differed from those of carp and trout in causing four times larger charge influx per excitation, which suggests that INa may also have a significant role in cardiac excitation-contraction coupling of the burbot heart. In summary, INa of fish cardiac myocytes shows thermal plasticity that is different in several respects in cold-dormant and cold-active species and thus has a physiologically meaningful role in supporting the variable life styles and habitat conditions of each species.
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Affiliation(s)
- Jaakko Haverinen
- University of Joensuu, Department of Biology, PO Box 111, 80101 Joensuu, Finland
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21
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Yamaoka K, Yuki T, Kawase K, Munemori M, Seyama I. Temperature-sensitive intracellular Mg2+ block of L-type Ca2+ channels in cardiac myocytes. Am J Physiol Heart Circ Physiol 2002; 282:H1092-101. [PMID: 11834508 DOI: 10.1152/ajpheart.00585.2001] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We examined the concentration-dependent blocking effects of intracellular Mg2+ on L-type Ca2+ channels in cardiac myocytes using the whole cell patch-clamp technique. The increase of L-type Ca2+ channel current (I(Ca)) (due to relief of Mg2+ block) occurred in two temporal phases. The rapid phase (runup) transiently appeared early (<5 min) in dialysis of the low-Mg2+ solution; the slow phase began later in dialysis (>10 min). Runup was not blocked by intracellular GTP (GTP(i)). The late phase of the I(Ca) increase (late I(Ca)) was suppressed by GTP(i) (0.4 mM) and was observed in myocytes of the guinea pig or frog at higher (32 or 24 degrees C, respectively) rather than lower temperatures (24 or 17.5 degrees C, respectively). At pMg = 6.0, raising the temperature from 24 to 32 degrees C evoked late I(Ca) with a Q10 of 14.5. Restoring the temperature to 24 degrees C decreased I(Ca) with a Q10 of only 2.4. The marked difference in the Q10 values indicated that late I(Ca) (pMg = 5-6) is an irreversible phenomenon. Phosphorylation suppressed the intracellular [Mg2+] dependency of late I(Ca). This effect of phosphorylation together with the inhibitory action of GTP(i) on Mg2+-dependent blocking of I(Ca) are common properties of mammalian and amphibian cardiomyocytes.
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Affiliation(s)
- Kaoru Yamaoka
- Department of Physiology, School of Medicine, Hiroshima University, Minami-Ku, Hiroshima 734-8551, Japan.
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22
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Rome LC, Swank DM. The influence of thermal acclimation on power production during swimming. I. In vivo stimulation and length change pattern of scup red muscle. J Exp Biol 2001; 204:409-18. [PMID: 11171294 DOI: 10.1242/jeb.204.3.409] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Ectothermal animals are able to locomote in a kinematically similar manner over a wide range of temperatures. It has long been recognized that there can be a significant reduction in the power output of muscle during swimming at low temperatures because of the reduced steady-state (i.e. constant activation and shortening velocity) power-generating capabilities of muscle. However, an additional reduction in power involves the interplay between the non-steady-state contractile properties of the muscles (i.e. the rates of activation and relaxation) and the in vivo stimulation and length change pattern the muscle undergoes during locomotion. In particular, it has been found that isolated scup (Stenotomus chrysops) red muscle working under in vivo stimulus and length change conditions (measured in warm-acclimated scup swimming at low temperatures) generates very little power for swimming. Even though the relaxation of the muscle has slowed greatly, warm-acclimated fish swim with the same tail-beat frequencies and the same stimulus duty cycles at cold temperatures, thereby not affording the slow-relaxing muscle any extra time to relax. We hypothesize that considerable improvement in the power output of the red muscle at low temperatures could be achieved if cold acclimation resulted in either a faster muscle relaxation rate or in the muscle being given more time to relax (e.g. by shortening the stimulus duration or reducing the tail-beat frequency). We test these hypotheses in this paper and the accompanying paper. Scup were acclimated to 10 degrees C (cold-acclimated) and 20 degrees C (warm-acclimated) for at least 6 weeks. Electromyograms (EMGs) and high-speed cine films were taken of fish swimming steadily at 10 degrees C and 20 degrees C. At 10 degrees C, we found that, although there were no differences in tail-beat frequency, muscle strain or stimulation phase between acclimation groups, cold-acclimated scup had EMG duty cycles approximately 20 % shorter than warm-acclimated scup. In contrast at 20 degrees C, there was no difference between acclimation groups in EMG duty cycle, nor in any other muscle length change or stimulation parameter. Thus, in response to cold acclimation, there appears to be a reduction in EMG duty cycle at low swimming temperatures that is probably due to an alteration in the operation of the pattern generator. This novel acclimation probably improves muscle power output at low temperatures compared with that of warm-acclimated fish, an expectation we test in the accompanying paper using the work-loop technique.
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Affiliation(s)
- L C Rome
- Department of Biology and Department of Physiology, University of Pennsylvania, Philadelphia, PA 19104, USA.
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23
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Abstract
Catecholamines have previously been detected in numerous tissues and are thought to control a wide variety of physiological functions in bivalve molluscs. In the present study, alumina extraction and high-performance liquid chromatography reveal the presence of significant concentrations of 3,4-dihydroxyphenylalanine (DOPA), dopamine, and 3,4-dihydroxyphenylacetic acid (DOPAC) in the hemolymph of the sea scallop, Placopecten magellanicus. The concentration of dopamine in the hemolymph averaged 223.8 ng/ml, (+/-48.4, SEM), equivalent to 10(-7) to 10(-6) M. Neither epinephrine nor norepinephrine was reliably detected in significant quantities. Previous studies have demonstrated physiological responses to dopamine with thresholds of 10(-9) to 10(-6) M, thus suggesting that this catecholamine may have an endocrine function. Furthermore, monitoring hemolymph concentrations of catechols might provide a sensitive measure of the physiological status of bivalves. For example, drugs known to affect catechol concentrations in other tissues also effect hemolymph levels. Administration of monoamine oxidase inhibitors such as pargyline, deprenyl, and clorgyline at 10(-4) M for 1 day of incubation followed by a 2-day wash resulted in decreased hemolymph concentrations of DOPAC and increased concentrations of its precursors, DOPA and dopamine. Incubation in 10(-4) M 3,5-dinitrocatechol, a catecholamine-O-methyl transferase blocker, for 1 day followed by a 2-day wash significantly increased the concentration of dopamine and DOPAC in the hemolymph. Scallops incubated in 10(-5) M alpha-methyl-p-tyrosine, a blocker of tyrosine hydroxylase, for 1 day followed by a 3-day wash in artificial seawater had significantly reduced concentrations of DOPA, dopamine, and DOPAC in the hemolymph. In addition to responding to pharmacological agents, dopamine levels also decreased significantly following thermal induction of spawning, thus suggesting that hemolymph concentrations of catechols might provide indices of reproductive activity and/or stress.
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Affiliation(s)
- A K Pani
- Department of Physiology and Biophysics, Dalhousie University, Halifax, Nova Scotia, B3H 4H7, Canada
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Neumeister H, Ripley B, Preuss T, Gilly WF. Effects of temperature on escape jetting in the squid Loligo opalescens. J Exp Biol 2000; 203:547-57. [PMID: 10637183 DOI: 10.1242/jeb.203.3.547] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
In Loligo opalescens, a sudden visual stimulus (flash) elicits a stereotyped, short-latency escape response that is controlled primarily by the giant axon system at 15 C. We used this startle response as an assay to examine the effects of acute temperature changes down to 6 C on behavioral and physiological aspects of escape jetting. In free-swimming squid, latency, distance traveled and peak velocity for single escape jets all increased as temperature decreased. In restrained squid, intra-mantle pressure transients during escape jets increased in latency, duration and amplitude at low temperature. Recordings of stellar nerve activity revealed repetitive firing of the giant motor axon accompanied by increased activity in the non-giant motor axons that run in parallel. Selective stimulation of giant and non-giant motor axons in isolated nerve-muscle preparations failed to show the effects seen in vivo, i.e. increased peak force and increased neural activity at low temperature. Taken together, these results suggest that L. opalescens is able to compensate escape jetting performance for the effects of acute temperature reduction. A major portion of this compensation appears to occur in the central nervous system and involves alterations in the recruitment pattern of both the giant and non-giant axon systems.
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Affiliation(s)
- H Neumeister
- Hopkins Marine Station of Stanford University, Department of Biological Science, Pacific Grove, CA 93950, USA.
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25
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Pearson T, Hyde D, Bowler K. Heterologous acclimation: a novel approach to the study of thermal acclimation in the crab Cancer pagurus. THE AMERICAN JOURNAL OF PHYSIOLOGY 1999; 277:R24-30. [PMID: 10409254 DOI: 10.1152/ajpregu.1999.277.1.r24] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The control of the attainment of acclimation in Cancer pagurus has been studied. Homologous (8 or 22 degrees C) and heterologous acclimation [central nervous system (CNS) and periphery of crabs simultaneously held at 8 or 22 degrees C] were used. The dependence of electrophysiological parameters of dactylopodite closer muscles of walking legs on nerve stimulation was determined between 6 and 26 degrees C. Muscle resting potential (RP) hyperpolarized linearly with increasing measurement temperatures and showed a 69% compensation between 8 and 22 degrees C on homologous acclimation. With the CNS temperature constant at 8 degrees C, the leg muscle RP showed a 72% compensation on heterologous acclimation to 8 and 22 degrees C; when CNS temperature was constant at 22 degrees C, leg muscle RP showed a 48% compensation on heterologous acclimation to 8 and 22 degrees C. In homologous acclimation, the shape of the excitatory junction potential vs. temperature relationship was characteristic of acclimation temperature. In heterologous acclimation, the shape of this plot was related to the temperature experienced by the leg and not by the CNS. Thus acclimation was principally dependent on local tissue temperature and was relatively independent of CNS or hormonal influences.
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Affiliation(s)
- T Pearson
- Department of Biological Sciences, University of Durham, Durham DH1 3LE, United Kingdom
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26
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Cuculescu M, Pearson T, Hyde D, Bowler K. Heterothermal acclimation: an experimental paradigm for studying the control of thermal acclimation in crabs. Proc Natl Acad Sci U S A 1999; 96:6501-5. [PMID: 10339617 PMCID: PMC26911 DOI: 10.1073/pnas.96.11.6501] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A method for the study of the control of the attainment of thermal acclimation has been applied to the crabs, Cancer pagurus and Carcinus maenas. Crabs were heterothermally acclimated by using an anterior-posterior partition between two compartments, one at 8 degrees C and the other at 22 degrees C. One compartment held a three-quarter section of the crab including the central nervous system (CNS), eye stalks, and ipsilateral legs; the other held a quarter section including the contralateral legs. Criteria used to assess the acclimation responses were comparisons of muscle plasma membrane fatty acid composition and "fluidity." In both species, the major fatty acids of phosphatidylcholine were 16:0, 18:1, 20:5, and 22:6, whereas phosphatidylethanolamine contained significantly less 16:0 but more 18:0; these fatty acids comprised 80% of the total. Differences in fatty acid composition were demonstrated between fractions obtained from the ipsilateral and contralateral legs from the same heterothermally acclimated individual. In all acclimation states (except 22CNS, phosphatidylcholine fraction), membrane lipid saturation was significantly increased with acclimation at 22 degrees as compared with 8 degrees C. Membrane fluidity was determined by using 1,3-diphenyl-1,3,5 hexatriene (DPH) fluorescence polarization. In both species, membranes from legs held at 8 degrees were more fluid than from legs held at 22 degrees C irrespective of the acclimation temperature of the CNS. Heterothermal acclimation demonstrated that leg muscle membrane composition and fluidity respond primarily to local temperature and were not predominately under central direction. The responses between 8 degrees C- and 22 degrees C-acclimated legs were more pronounced when the CNS was cold-acclimated, so a central influence cannot be excluded.
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Affiliation(s)
- M Cuculescu
- Department of Biological Sciences, The University of Durham, Durham City DH1 3LE, United Kingdom
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27
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Effects of Cooling on the Abdominal Ganglion Muscle Preparation of Macruran Decapod Crustaceans. Comp Biochem Physiol A Mol Integr Physiol 1998. [DOI: 10.1016/s1095-6433(98)01027-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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28
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Lehti-Koivunen SM, Kivivuori LA. Fluidity of Neuronal Membranes of Crayfish (Astacus astacus L.) Acclimated to 5°C and 20°C. Comp Biochem Physiol A Mol Integr Physiol 1998. [DOI: 10.1016/s1095-6433(98)01014-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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29
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Hazel J. Thermal Adaptation in Biological Membranes: Beyond Homeoviscous Adaptation. THERMOBIOLOGY 1997. [DOI: 10.1016/s1569-2558(08)60075-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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30
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The short and long-term effects of temperature on the dynamic range of signalling in horizontal cells of carp retina. J Therm Biol 1995. [DOI: 10.1016/0306-4565(94)00059-r] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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31
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Macdonald AG. The homeoviscous theory of adaptation applied to excitable membranes: a critical evaluation. BIOCHIMICA ET BIOPHYSICA ACTA 1990; 1031:291-310. [PMID: 2171657 DOI: 10.1016/0304-4157(90)90014-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- A G Macdonald
- Department of Physiology, Marischal College, University of Aberdeen, U.K
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32
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Muscle potentials and temperature acclimation and acclimatization in flight muscles of workers and drones of Apis mellifera. J Therm Biol 1990. [DOI: 10.1016/0306-4565(90)90017-c] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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33
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Hazel JR. Cold Adaptation in Ectotherms: Regulation of Membrane Function and Cellular Metabolism. ADVANCES IN COMPARATIVE AND ENVIRONMENTAL PHYSIOLOGY 1989. [DOI: 10.1007/978-3-642-74078-7_1] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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34
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Conradi NG, Nyström B, Hamberger A, Sourander P. Changes in brain temperature and free amino acids in normal and protein deprived suckling rats exposed to room temperature. Neurochem Res 1988; 13:657-61. [PMID: 3137484 DOI: 10.1007/bf00973284] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Previous reports on early-induced protein-calorie malnutrition (PCM) in rats have indicated alterations in the concentration of free amino acids and of protein synthesis in the brain. Recently it was shown that early-induced protein deprivation (PD) retards the development of thermoregulation. This resulted in a failure to maintain a normal rectal temperature after short exposure to room temperature (+22 degrees C) still at the age of 20-25 days corresponding to changes seen in normal rats at an age of 10-15 days. In the present study, 20-day old PD and normal rats where examined with regard to the effect of exposure to room temperature on brain temperature and on brain free amino acids. The results show a similar reduction in brain and rectal temperature of the PD rats occurring within 30 minutes after exposure to room temperature. The reduction was in the range of 5 degrees C. PD rats kept in room temperature for 5 hours and then allowed to recover at 32.5 degrees C showed a slow increase in brain and rectal temperature but normal temperatures were not reached even after 1 hour. The concentration of free amino acids in the brain was examined in rats kept for 1 hour at room temperature or at 32.5 degrees C. In the PD rats kept at 32.5 degrees C, free aspartate and glutamate were reduced whereas taurine, GABA and glycine were increased as compared to their corresponding control rats. As a result of the reduced brain temperature in PD rats exposed to room temperature there was a reduction in free asparagine.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- N G Conradi
- Department of Pathology, Sahlgren Hospital, Göteborg, Sweden
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35
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Ritchart J, Hutchison V. The effects of ATP and cAMP on the thermal tolerance of the mudpuppy, Necturus maculosus. J Therm Biol 1986. [DOI: 10.1016/0306-4565(86)90017-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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36
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Jones KA. Temperature dependent attraction by goldfish to a chemical feeding cue presented alone and in combination with heated water. Physiol Behav 1984; 33:509-15. [PMID: 6522471 DOI: 10.1016/0031-9384(84)90363-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
An eight cell multiple-choice experiment was used to investigate the influence of temperature on the locomotor response of goldfish (Carassius auratus) to a chemical feeding cue. When a food extract was infused into a single cell at ambient temperatures of 26, 28, 30, 32, and 34 degrees C (ambient temperature=acclimation temperature) the goldfish spent more time in the extract cell than three similarly outfitted dummy cells at all temperatures, but the intensity of their attraction varied over the thermal interval. Attraction was highest at 28 degrees C and gradually declined to its lowest level by 34 degrees C. Goldfish acclimated and tested at 26 degrees C spent more time visiting a combination of food extract and heated water (H+E) than either food extract (E) or heated water (H) alone. The preference for H+E over H and E increased with the temperature differential between heated and ambient waters. Successive increased in acclimation/ambient temperature (30, 32, and 34 degrees C) extinguished the differences between H+E and H and E but did not eliminate the attraction for the thermal and chemical stimuli, per se. The importance of temperature in the variability of chemoreceptive behavior and the interaction between chemical and thermal stimuli are discussed.
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37
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Schoffeniels E. Les bases moléculaires de l'écologie. BIOCHEM SYST ECOL 1984. [DOI: 10.1016/0305-1978(84)90048-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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38
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Variability in brain ganglioside composition: A further molecular mechanism beside serum antifreeze-glykoproteins for adaptation to cold in Antarctic and Arctic-boreal fishes. Polar Biol 1984. [DOI: 10.1007/bf00258155] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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39
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Brauer R, Sidelyova V, Dail M, Galazii G, Roer R. Physiological adaptation of cottoid fishes of lake baikal to abyssal depths. ACTA ACUST UNITED AC 1984. [DOI: 10.1016/0300-9629(84)90188-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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40
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Mühleisen M, Hilbig R, Rahmann H. Brain gangliosides in hibernating dormice (Glis glis) and cold-exposed laboratory mice. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. B, COMPARATIVE BIOCHEMISTRY 1984; 78:335-41. [PMID: 6467899 DOI: 10.1016/0305-0491(84)90040-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The concentration of proteins, sialo-glycoproteins and gangliosides and the ganglioside composition of 8 brain regions from normothermic and hibernating fat dormice (Glis glis) and from laboratory mice being acclimated to 6, 22 and 28 degrees C were investigated. During hibernation the concentration of sialo-glycoproteins and gangliosides decreased significantly in brain of dormice; the protein content remained uninfluenced. Cold-exposure of laboratory mice yielded generally a slightly decreased sialo-glycoprotein concentration in brain; the data on ganglioside concentration in the CNS were not uniform. The ganglioside composition of brain of laboratory mice being kept at different environmental temperatures did not show any alterations. The brain gangliosides of hibernating dormice in contrast to their normothermic counterparts are more polar (higher amount of GTlb and GQlb.). Most striking is the complete absence of a distinct ganglioside fraction (O-acetylated-GTlb) during hibernation. Brain gangliosides of normothermic dormice were found to be more sensitive against neuraminidase treatment than those of hibernating animals. The results are discussed with regard to modulatory functions of neuronal gangliosides for the process of synaptic transmission during seasonal adaptation.
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Mohamed MI, Aly MS, Selim MF. Effects of ambient temperature on brain acetylcholinesterase activity and protein content in three Egyptian vertebrates. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. C, COMPARATIVE PHARMACOLOGY AND TOXICOLOGY 1983; 76:127-30. [PMID: 6139239 DOI: 10.1016/0742-8413(83)90054-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Exposure to cold caused an increase in AChE activity of the different brain regions of both Arvicanthis and Columbia and a decrease in the enzyme activity of Scincus midbrain. Heat exposure provoked variable changes in AChE activity of the various brain regions of the three experimental species. The changes in AChE activities may be one of the mechanisms by which birds and mammals tend to acclimatize themselves to various forms of stress. In reptiles, AChE activity varied with changes in ambient temperature and this is probably due to the adaptive significance of thermally directed changes in enzyme substrate affinity.
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42
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Thermal limits of neuromuscular function in an antarctic fish. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 1982. [DOI: 10.1007/bf00609848] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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43
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Rahmann H, Hilbig R. The possible functional role of neuronal gangliosides in temperature adaptation of vertebrates. J Therm Biol 1981. [DOI: 10.1016/0306-4565(81)90020-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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44
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45
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46
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Geiser F, Hilbig R, Rahmann H. Hibernation-induced changes in the ganglioside composition of dormice (Glis glis). J Therm Biol 1981. [DOI: 10.1016/0306-4565(81)90049-8] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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47
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Beaver R, Brauer R. Pressure/temperature interactions in relation to development of high pressure convulsions in ectotherm vertebrates. ACTA ACUST UNITED AC 1981. [DOI: 10.1016/0300-9629(81)90153-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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48
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Hill MW, Neale E, Bangham AD. Acute tolerance to the effects of n-butanol and n-hexanol in goldfish. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 1981. [DOI: 10.1007/bf00605476] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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49
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Zecević D, Levitan H. Temperature acclimation: effects on membrane physiology of an identified snail neuron. THE AMERICAN JOURNAL OF PHYSIOLOGY 1980; 239:C47-57. [PMID: 7435551 DOI: 10.1152/ajpcell.1980.239.3.c47] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The neuronal basis for thermal acclimation was examined by comparing the short- and long-term effects of temperature change on the physiological properties of an identified neuron in the isolated ganglion of Hexis aspersa. Using intracellular electrophysiological techniques, we found that the frequency of spontaneous action potentials and excitability of neurons from warm-acclimated animals was depressed by abruptly cooling from 20 to 5 degrees C. After a 2-wk period of acclimation to 5 degrees C, the levels of spontaneous activity and excitability were comparable to those of warm-acclimated neurons at 20 degrees C. Conversely, abrupt warming of neurons from cold-acclimated animals greatly increased the frequency of spontaneous activity, but after acclimation to 20 degrees C the frequency decreased. Although the duration of the action potential and the cell's electrogenic Na-K pump were temperature sensitive, thermal acclimation had no obvious effects on these parameters. Membrane permeability to Na and PNa/PK decreased with cooling, whereas PRb/PK and PCs/PK increased. Warming had the opposite effect on the relative alkali cation permeability (PX/PK). With acclimation PX/PK underwent compensatory changes.
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50
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Rahmann H, Schmidt W, Schmidt B. Influence of long-term thermal acclimation on the conditionability of fish. J Therm Biol 1980. [DOI: 10.1016/0306-4565(80)90034-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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