1
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Beigloo F, Davidson CJ, Gjonaj J, Perrine SA, Kenney JW. Individual differences in the boldness of female zebrafish are associated with alterations in serotonin function. J Exp Biol 2024; 227:jeb247483. [PMID: 38842023 PMCID: PMC11213521 DOI: 10.1242/jeb.247483] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Accepted: 05/14/2024] [Indexed: 06/07/2024]
Abstract
One of the most prevalent axes of behavioral variation in both humans and animals is risk taking, where individuals that are more willing to take risk are characterized as bold while those that are more reserved are regarded as shy. Brain monoamines (i.e. serotonin, dopamine and noradrenaline) have been found to play a role in a variety of behaviors related to risk taking. Using zebrafish, we investigated whether there was a relationship between monoamine function and boldness behavior during exploration of a novel tank. We found a correlation between serotonin metabolism (5-HIAA:5-HT ratio) and boldness during the initial exposure to the tank in female animals. The DOPAC:DA ratio correlated with boldness behavior on the third day in male fish. There was no relationship between boldness and noradrenaline. To probe differences in serotonergic function in bold and shy fish, we administered a selective serotonin reuptake inhibitor, escitalopram, and assessed exploratory behavior. We found that escitalopram had opposing effects on thigmotaxis in bold and shy female animals: the drug caused bold fish to spend more time near the center of the tank and shy fish spent more time near the periphery. Taken together, our findings indicate that variation in serotonergic function has sex-specific contributions to individual differences in risk-taking behavior.
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Affiliation(s)
- Fatemeh Beigloo
- Department of Biological Sciences, Wayne State University, Detroit, MI 48202, USA
| | - Cameron J. Davidson
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, Detroit, MI 48201, USA
| | - Joseph Gjonaj
- Department of Biological Sciences, Wayne State University, Detroit, MI 48202, USA
| | - Shane A. Perrine
- Department of Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, Detroit, MI 48201, USA
| | - Justin W. Kenney
- Department of Biological Sciences, Wayne State University, Detroit, MI 48202, USA
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2
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Han J, Ho TW, Stine JM, Overton SN, Herberholz J, Ghodssi R. Simultaneous Dopamine and Serotonin Monitoring in Freely Moving Crayfish Using a Wireless Electrochemical Sensing System. ACS Sens 2024; 9:2346-2355. [PMID: 38713172 DOI: 10.1021/acssensors.3c02304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
Dopamine (DA) and serotonin (5-HT) are neurotransmitters that regulate a wide range of physiological and behavioral processes. Monitoring of both neurotransmitters with real-time analysis offers important insight into the mechanisms that shape animal behavior. However, bioelectronic tools to simultaneously monitor DA and 5-HT interactive dynamics in freely moving animals are underdeveloped. This is mainly due to the limited sensor sensitivity with miniaturized electronics. Here, we present a semi-implantable electrochemical device achieved by integrating a multi-surface-modified carbon fiber microelectrode with a miniaturized potentiostat module to detect DA and 5-HT in vivo with high sensitivity and selectivity. Specifically, carbon fiber microelectrodes were modified through electrochemical treatment and surface coatings to improve sensitivity, selectivity, and antifouling properties. A customized, lightweight potentiostat module was developed for untethered electrochemical measurements. Integrated with the microelectrode, the microsystem is compact (2.8 × 2.3 × 2.1 cm) to minimize its impacts on animal behavior and achieved simultaneous detection of DA and 5-HT with sensitivities of 48.4 and 133.0 nA/μM, respectively, within submicromolar ranges. The system was attached to the crayfish dorsal carapace, allowing electrode implantation into the heart of a crayfish to monitor DA and 5-HT dynamics, followed by drug injections. The semi-implantable biosensor system displayed a significant increase in oxidation peak currents after DA and 5-HT injections. The device successfully demonstrated the application for in vivo simultaneous monitoring of DA and 5-HT in the hemolymph (i.e., blood) of freely behaving crayfish underwater, yielding a valuable experimental tool to expand our understanding of the comodulation of DA and 5-HT.
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Affiliation(s)
- Jinjing Han
- Department of Electrical and Computer Engineering, University of Maryland, College Park, Maryland 20742, United States
- Institute for Systems Research, University of Maryland, College Park, Maryland 20742, United States
- Robert E. Fischell Institute for Biomedical Devices, University of Maryland, College Park, Maryland 20742, United States
| | - Ta-Wen Ho
- Department of Psychology, University of Maryland, College Park, Maryland 20742, United States
- Program in Neuroscience and Cognitive Science, University of Maryland, College Park, Maryland 20742, United States
| | - Justin M Stine
- Department of Electrical and Computer Engineering, University of Maryland, College Park, Maryland 20742, United States
- Institute for Systems Research, University of Maryland, College Park, Maryland 20742, United States
- Robert E. Fischell Institute for Biomedical Devices, University of Maryland, College Park, Maryland 20742, United States
| | - Sydney N Overton
- Department of Electrical and Computer Engineering, University of Maryland, College Park, Maryland 20742, United States
- Institute for Systems Research, University of Maryland, College Park, Maryland 20742, United States
- Robert E. Fischell Institute for Biomedical Devices, University of Maryland, College Park, Maryland 20742, United States
| | - Jens Herberholz
- Department of Psychology, University of Maryland, College Park, Maryland 20742, United States
- Program in Neuroscience and Cognitive Science, University of Maryland, College Park, Maryland 20742, United States
| | - Reza Ghodssi
- Department of Electrical and Computer Engineering, University of Maryland, College Park, Maryland 20742, United States
- Institute for Systems Research, University of Maryland, College Park, Maryland 20742, United States
- Robert E. Fischell Institute for Biomedical Devices, University of Maryland, College Park, Maryland 20742, United States
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3
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Sun T, Du YY, Zhang YQ, Tian QQ, Li X, Yu JY, Guo YY, Liu QQ, Yang L, Wu YM, Yang Q, Zhao MG. Activation of GPR55 Ameliorates Maternal Separation-Induced Learning and Memory Deficits by Augmenting 5-HT Synthesis in the Dorsal Raphe Nucleus of Juvenile Mice. ACS OMEGA 2024; 9:21838-21850. [PMID: 38799363 PMCID: PMC11112691 DOI: 10.1021/acsomega.3c08934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 04/16/2024] [Accepted: 04/24/2024] [Indexed: 05/29/2024]
Abstract
Maternal separation (MS) represents a profound early life stressor with enduring impacts on neuronal development and adult cognitive function in both humans and rodents. MS is associated with persistent dysregulations in neurotransmitter systems, including the serotonin (5-HT) pathway, which is pivotal for mood stabilization and stress-coping mechanisms. Although the novel cannabinoid receptor, GPR55, is recognized for its influence on learning and memory, its implications on the function and synaptic dynamics of 5-HT neurons within the dorsal raphe nucleus (DRN) remain to be elucidated. In this study, we sought to discern the repercussions of GPR55 activation on 5-HT synthesis within the DRN of adult C57BL/6J mice that experienced MS. Concurrently, we analyzed potential alterations in excitatory synaptic transmission, long-term synaptic plasticity, and relevant learning and memory outcomes. Our behavioral assessments indicated a marked amelioration in MS-induced learning and memory deficits following GPR55 activation. In conjunction with this, we noted a substantial decrease in 5-HT levels in the MS model, while GPR55 activation stimulated tryptophan hydroxylase 2 synthesis and fostered the release of 5-HT. Electrophysiological patch-clamp analyses highlighted the ability of GPR55 activation to alleviate MS-induced cognitive deficits by modulating the frequency and magnitude of miniature excitatory postsynaptic currents within the DRN. Notably, this cognitive enhancement was underpinned by the phosphorylation of both NMDA and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors. In summary, our findings underscore the capacity of GPR55 to elevate 5-HT synthesis and modify synaptic transmissions within the DRN of juvenile mice, positing GPR55 as a promising therapeutic avenue for ameliorating MS-induced cognitive impairment.
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Affiliation(s)
- Ting Sun
- Precision
Pharmacy & Drug Development Center, Department of Pharmacy, The Second Affiliated Hospital of Air Force Medical
University, Xi’an 710038, China
| | - Ya-Ya Du
- Precision
Pharmacy & Drug Development Center, Department of Pharmacy, The Second Affiliated Hospital of Air Force Medical
University, Xi’an 710038, China
| | - Yong-Qiang Zhang
- Department
of Chinese Materia Medica and Natural Medicines, School of Pharmacy, Air Force Medical University, Xi’an 710032, China
| | - Qin-Qin Tian
- Department
of Chemistry, School of Pharmacy, Air Force
Medical University, Xi’an 710032, China
| | - Xi Li
- Precision
Pharmacy & Drug Development Center, Department of Pharmacy, The Second Affiliated Hospital of Air Force Medical
University, Xi’an 710038, China
| | - Jiao-Yan Yu
- Precision
Pharmacy & Drug Development Center, Department of Pharmacy, The Second Affiliated Hospital of Air Force Medical
University, Xi’an 710038, China
| | - Yan-Yan Guo
- Precision
Pharmacy & Drug Development Center, Department of Pharmacy, The Second Affiliated Hospital of Air Force Medical
University, Xi’an 710038, China
| | - Qing-Qing Liu
- Precision
Pharmacy & Drug Development Center, Department of Pharmacy, The Second Affiliated Hospital of Air Force Medical
University, Xi’an 710038, China
| | - Le Yang
- Precision
Pharmacy & Drug Development Center, Department of Pharmacy, The Second Affiliated Hospital of Air Force Medical
University, Xi’an 710038, China
| | - Yu-Mei Wu
- Department
of Pharmacology, School of Pharmacy, Air
Force Medical University, Xi’an 710032, China
| | - Qi Yang
- Precision
Pharmacy & Drug Development Center, Department of Pharmacy, The Second Affiliated Hospital of Air Force Medical
University, Xi’an 710038, China
| | - Ming-Gao Zhao
- Precision
Pharmacy & Drug Development Center, Department of Pharmacy, The Second Affiliated Hospital of Air Force Medical
University, Xi’an 710038, China
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4
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Beigloo F, Davidson CJ, Gjonaj J, Perrine SA, Kenney JW. Individual differences in the boldness of female zebrafish are associated with alterations in serotonin function. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.13.580160. [PMID: 38405806 PMCID: PMC10888793 DOI: 10.1101/2024.02.13.580160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/27/2024]
Abstract
One of the most prevalent axes of behavioral variation in both humans and animals is risk taking, where individuals that are more willing to take risk are characterized as bold while those that are more reserved as shy. Brain monoamines (i.e., serotonin, dopamine, and norepinephrine) have been found to play a role in a variety of behaviors related to risk taking. Genetic variation related to monoamine function have also been linked to personality in both humans and animals. Using zebrafish, we investigated the relationship between monoamine function and boldness behavior during exploration of a novel tank. We found a sex-specific correlation between serotonin metabolism (5-HIAA:5-HT ratio) and boldness that was limited to female animals; there were no relationships between boldness and dopamine or norepinephrine. To probe differences in serotonergic function, we administered a serotonin reuptake inhibitor, escitalopram, to bold and shy fish, and assessed their exploratory behavior. We found that escitalopram had opposing effects on thigmotaxis in female animals with bold fish spending more time near the center of the tank and shy fish spent more time near the periphery. Taken together, our findings suggest that variation in serotonergic function makes sex-specific contributions to individual differences in risk taking behavior.
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Affiliation(s)
- Fatemeh Beigloo
- Department of Biological Sciences Wayne State University, Detroit, MI 48202, USA
| | - Cameron J Davidson
- Department of Psychiatry and Behavioral Neurosciences Wayne State University School of Medicine, Detroit, MI 48201, USA
- Current address: Department of Foundational Medical Studies, Oakland University William Beaumont School of Medicine, Rochester, MI 48309, USA
| | - Joseph Gjonaj
- Department of Biological Sciences Wayne State University, Detroit, MI 48202, USA
| | - Shane A Perrine
- Department of Psychiatry and Behavioral Neurosciences Wayne State University School of Medicine, Detroit, MI 48201, USA
| | - Justin W Kenney
- Department of Biological Sciences Wayne State University, Detroit, MI 48202, USA
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5
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Beaulieu M. Capturing wild animal welfare: a physiological perspective. Biol Rev Camb Philos Soc 2024; 99:1-22. [PMID: 37635128 DOI: 10.1111/brv.13009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Revised: 08/07/2023] [Accepted: 08/07/2023] [Indexed: 08/29/2023]
Abstract
Affective states, such as emotions, are presumably widespread across the animal kingdom because of the adaptive advantages they are supposed to confer. However, the study of the affective states of animals has thus far been largely restricted to enhancing the welfare of animals managed by humans in non-natural contexts. Given the diversity of wild animals and the variable conditions they can experience, extending studies on animal affective states to the natural conditions that most animals experience will allow us to broaden and deepen our general understanding of animal welfare. Yet, this same diversity makes examining animal welfare in the wild highly challenging. There is therefore a need for unifying theoretical frameworks and methodological approaches that can guide researchers keen to engage in this promising research area. The aim of this article is to help advance this important research area by highlighting the central relationship between physiology and animal welfare and rectify its apparent oversight, as revealed by the current scientific literature on wild animals. Moreover, this article emphasises the advantages of including physiological markers to assess animal welfare in the wild (e.g. objectivity, comparability, condition range, temporality), as well as their concomitant limitations (e.g. only access to peripheral physiological markers with complex relationships with affective states). Best-practice recommendations (e.g. replication and multifactorial approaches) are also provided to allow physiological markers to be used most effectively and appropriately when assessing the welfare of animals in their natural habitat. This review seeks to provide the foundation for a new and distinct research area with a vast theoretical and applied potential: wild animal welfare physiology.
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Affiliation(s)
- Michaël Beaulieu
- Wild Animal Initiative, 5123 W 98th St, 1204, Minneapolis, MN, 55437, USA
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6
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Elwood RW. Hermit crabs, shells, and sentience. Anim Cogn 2022; 25:1241-1257. [PMID: 35199235 DOI: 10.1007/s10071-022-01607-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 01/25/2022] [Accepted: 02/14/2022] [Indexed: 12/22/2022]
Abstract
Hermit crabs have an intimate relationship with gastropod shells and show numerous activities by which they locate, select, and change shells in different contexts. They gather information about new shells and update information about their existing shells. This involves integration of different sensory modalities, memory-formation, and comparison of the overall value of each shell. Crabs also fight to get shells from other crabs, and again they gather information about the shell qualities and the opponent. Attacking crabs monitor their fight performance, and defenders are influenced by attacker activities, and both crabs are influenced by the gain or loss that might be made by swapping shells. Swapping shells involves the defender being naked for a short period. Leaving a shell also occurs if the shell is experimentally fixed in place or buried in sand or if small electric shocks are applied to the abdomen, and the quality of the current shell is traded-off against escaping possible asphyxiation or the aversive shocks. Hermit crabs show remarkable abilities, involving future planning, with respect to recognizing the shape and size of shells, and how they limit their passage through environmental obstructions. They also assess if shells might become available and wait for that to happen. Groups of crabs arrange themselves in size order so that orderly transfer of shells might occur down a line of crabs. These observations are discussed in the light of complex perceptual and cognitive abilities, and the possibility of sentience and awareness is discussed.
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Affiliation(s)
- Robert W Elwood
- School of Biological Sciences, Queen's University, Belfast, BT9 5DL, UK.
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7
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Florkowski MR, Yorzinski JL. Dopamine receptor activation elicits a possible stress-related coping behavior in a wild-caught songbird. PeerJ 2022; 10:e13520. [PMID: 35795178 PMCID: PMC9252180 DOI: 10.7717/peerj.13520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Accepted: 05/09/2022] [Indexed: 01/17/2023] Open
Abstract
Animals experience stress throughout their lives and exhibit both physiological and behavioral responses to cope with it. The stress response can become harmful when prolonged and increasing evidence suggests that dopamine plays a critical role in extinguishing the stress response. In particular, activation of the D2 dopamine receptor reduces glucocorticoids and increases coping behavior, i.e., behavioral responses to adverse stimuli that reduce the harmful effects of stress. However, few studies have examined the effects of dopamine on the stress responses of wild species. We therefore tested the hypothesis that activation of the D2 dopamine receptor influences coping-like behavior in a wild-caught species. We recorded behavior of house sparrows (Passer domesticus) before and after they received injections of D2 dopamine agonists, D2 dopamine antagonists, or saline. House sparrows are common in urban environments and understanding how they cope with stress may help us better understand how animals cope with urban stressors. We found that the birds significantly increased biting of inanimate objects after the agonist but there was no change following the antagonist or saline. The biting of inanimate objects may be a mechanism of behavioral coping. This change in biting behavior was not correlated with general movement. This study supports the hypothesis that D2 dopamine receptor activation is involved in the regulation of the stress response in a wild bird.
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Affiliation(s)
- Melanie R. Florkowski
- Ecology and Evolutionary Biology Program, Texas A&M University, College Station, TX, United States
| | - Jessica L. Yorzinski
- Ecology and Evolutionary Biology Program, Texas A&M University, College Station, TX, United States,Department of Ecology and Conservation Biology, Texas A&M University, College Station, TX, United States
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8
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Mack D, Yevugah A, Renner K, Burrell BD. Serotonin mediates stress-like effects on responses to non-nociceptive stimuli in Hirudo. J Exp Biol 2022; 225:275639. [PMID: 35510636 PMCID: PMC9234501 DOI: 10.1242/jeb.243404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2021] [Accepted: 04/29/2022] [Indexed: 11/28/2022]
Abstract
Noxious stimuli can elicit stress in animals that produce a variety of adaptations including changes in responses to nociceptive and non-nociceptive sensory input. One example is stress-induced analgesia that may be mediated, in part, by the endocannabinoid system. However, endocannabinoids can also have pro-nociceptive effects. In this study, the effects of electroshock, one experimental approach for producing acute stress, were examined on responses to non-nociceptive mechanical stimuli and nociceptive thermal stimuli in the medicinal leech (Hirudo verbana). The electroshock stimuli did not alter the leeches’ responses to nociceptive stimuli, but did cause sensitization to non-nociceptive stimuli, characterized by a reduction in response threshold. These experiments were repeated with drugs that either blocked synthesis of the endocannabinoid transmitter 2-arachidonoylglycerol (2-AG) or transient receptor potential vanilloid (TRPV) channel, which is known to act as an endocannabinoid receptor. Surprisingly, neither treatment had any effect on responses following electroshock. However, the electroshock stimuli reliably increased serotonin (5-hydroxytryptamine or 5HT) levels in the H. verbana CNS. Injection of 5HT mimicked the effects of the electroshocks, sensitizing responses to non-nociceptive stimuli and having no effect on responses to nociceptive stimuli. Injections of the 5HT receptor antagonist methysergide reduced the sensitization effect to non-nociceptive stimuli after electroshock treatment. These results indicate that electroshocks enhance response to non-nociceptive stimuli but do not alter responses to nociceptive stimuli. Furthermore, while 5HT appears to play a critical role in this shock-induced sensitizing effect, the endocannabinoid system seems to have no effect. Summary: The role of serotonin and endocannabinoids in mediating the effects of potentially stress-inducing stimuli on Hirudo verbana’s response to nociceptive and non-nociceptive input.
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Affiliation(s)
- Danielle Mack
- Division of Basic Biomedical Sciences, University of South Dakota, USA.,Center for Brain and Behavior Research, University of South Dakota, USA
| | | | - Kenneth Renner
- Department of Biology, University of South Dakota, USA.,Center for Brain and Behavior Research, University of South Dakota, USA
| | - Brian D Burrell
- Division of Basic Biomedical Sciences, University of South Dakota, USA.,Center for Brain and Behavior Research, University of South Dakota, USA
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9
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Browning H, Birch J. Animal sentience. PHILOSOPHY COMPASS 2022; 17:e12822. [PMID: 35859762 PMCID: PMC9285591 DOI: 10.1111/phc3.12822] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 10/01/2021] [Accepted: 02/14/2022] [Indexed: 06/01/2023]
Abstract
'Sentience' sometimes refers to the capacity for any type of subjective experience, and sometimes to the capacity to have subjective experiences with a positive or negative valence, such as pain or pleasure. We review recent controversies regarding sentience in fish and invertebrates and consider the deep methodological challenge posed by these cases. We then present two ways of responding to the challenge. In a policy-making context, precautionary thinking can help us treat animals appropriately despite continuing uncertainty about their sentience. In a scientific context, we can draw inspiration from the science of human consciousness to disentangle conscious and unconscious perception (especially vision) in animals. Developing better ways to disentangle conscious and unconscious affect is a key priority for future research.
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Affiliation(s)
- Heather Browning
- Centre for Philosophy of Natural and Social ScienceLondon School of Economics and Political ScienceLondonUK
| | - Jonathan Birch
- Centre for Philosophy of Natural and Social ScienceLondon School of Economics and Political ScienceLondonUK
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10
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Kamada S, Nagayama T. Anxiety induces long-term memory forgetting in the crayfish. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2021; 207:459-467. [PMID: 33881581 DOI: 10.1007/s00359-021-01487-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 04/10/2021] [Accepted: 04/12/2021] [Indexed: 02/07/2023]
Abstract
When two male crayfish encounter, agonistic bouts are initiated and a winner-loser relationship is established. Larger animals are more likely to win with their physical advantage, but they are frequently beaten by small dominant animals with previous winning experience. This winner effect remains for several days. In mammals, anxiety impairs learning and induces memory forgetting. In this study, dominant crayfish were exposed to electrical shocks two days after their first win, after which they were paired with large or small naive opponents the following day. Our results showed that electrical shock-applied dominant animals were beaten by large naive opponents, but overcame small naive opponents, suggesting that electrical shocks cause animals to forget their previous winner effect. Electrical shocks appeared to elicit serotonin-mediated anxiety since electrical shocks had no effect on mianserin-injected dominant animals. A 0.5 µM serotonin injection induced a caused anxiety-like reaction, while a 1.0 µM serotonin injection-induced no changes in posture and walking activity. For pairings between dominant and naive animals 1 day after serotonin injection, 0.5 µM serotonin caused similar forgetting of the winner effect, but 1.0 µM serotonin had no effect. Serotonin of low concentrations mediated anxiety and stimulated forgetting of the winner's memory.
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Affiliation(s)
- Satomi Kamada
- Department of Biology, Faculty of Science, Yamagata University, Yamagata, 990-8560, Japan
| | - Toshiki Nagayama
- Department of Biology, Faculty of Science, Yamagata University, Yamagata, 990-8560, Japan.
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11
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Humane Slaughter of Edible Decapod Crustaceans. Animals (Basel) 2021; 11:ani11041089. [PMID: 33920380 PMCID: PMC8069407 DOI: 10.3390/ani11041089] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 03/30/2021] [Accepted: 04/06/2021] [Indexed: 01/29/2023] Open
Abstract
Simple Summary Decapods respond to noxious stimuli in ways that are consistent with the experience of pain; thus, we accept the need to provide a legal framework for their protection when they are used for human food. We review the main methods used to slaughter the major decapod crustaceans, highlighting problems posed by each method for animal welfare. The aim is to identify methods that are the least likely to cause suffering. These methods can then be recommended, whereas other methods that are more likely to cause suffering may be banned. We thus request changes in the legal status of this group of animals, to protect them from slaughter techniques that are not viewed as being acceptable. Abstract Vast numbers of crustaceans are produced by aquaculture and caught in fisheries to meet the increasing demand for seafood and freshwater crustaceans. Simultaneously, the public is increasingly concerned about current methods employed in their handling and killing. Recent evidence has shown that decapod crustaceans probably have the capacity to suffer because they show responses consistent with pain and have a relatively complex cognitive capacity. For these reasons, they should receive protection. Despite the large numbers of crustaceans transported and slaughtered, legislation protecting their welfare, by using agreed, standardized methods, is lacking. We review various stunning and killing systems proposed for crustaceans, and assess welfare concerns. We suggest the use of methods least likely to cause suffering and call for the implementation of welfare guidelines covering the slaughter of these economically important animals.
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12
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De Deurwaerdère P, Chagraoui A, Di Giovanni G. Serotonin/dopamine interaction: Electrophysiological and neurochemical evidence. PROGRESS IN BRAIN RESEARCH 2021; 261:161-264. [PMID: 33785130 DOI: 10.1016/bs.pbr.2021.02.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The interaction between serotonin (5-HT) and dopamine (DA) in the central nervous system (CNS) plays an important role in the adaptive properties of living animals to their environment. These are two modulatory, divergent systems shaping and regulating in a widespread manner the activity of neurobiological networks and their interaction. The concept of one interaction linking these two systems is rather elusive when looking at the mechanisms triggered by these two systems across the CNS. The great variety of their interacting mechanisms is in part due to the diversity of their neuronal origin, the density of their fibers in a given CNS region, the distinct expression of their numerous receptors in the CNS, the heterogeneity of their intracellular signaling pathway that depend on the cellular type expressing their receptors, and the state of activity of neurobiological networks, conditioning the outcome of their mutual influences. Thus, originally conceptualized as inhibition of 5-HT on DA neuron activity and DA neurotransmission, this interaction is nowadays considered as a multifaceted, mutual influence of these two systems in the regulation of CNS functions. These new ways of understanding this interaction are of utmost importance to envision the consequences of their dysfunctions underlined in several CNS diseases. It is also essential to conceive the mechanism of action of psychotropic drugs directly acting on their function including antipsychotic, antidepressant, antiparkinsonian, and drug of abuse together with the development of therapeutic strategies of Alzheimer's diseases, epilepsy, obsessional compulsive disorders. The 5-HT/DA interaction has a long history from the serendipitous discovery of antidepressants and antipsychotics to the future, rationalized treatments of CNS disorders.
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Affiliation(s)
- Philippe De Deurwaerdère
- Centre National de la Recherche Scientifique, Institut des Neurosciences Intégratives et Cognitives d'Aquitaine, UMR 5287, Bordeaux, France.
| | - Abdeslam Chagraoui
- Laboratory of Neuronal and Neuroendocrine Differentiation and Communication, Institute for Research and Innovation in Biomedicine of Normandy (IRIB), Normandie University, UNIROUEN, INSERM U1239, Rouen, France; Department of Medical Biochemistry, Rouen University Hospital, Rouen, France
| | - Giuseppe Di Giovanni
- Laboratory of Neurophysiology, Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, Msida, Malta; Neuroscience Division, School of Biosciences, Cardiff University, Cardiff, United Kingdom.
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13
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Ahmed WMS, Abdel-Azeem NM, Ibrahim MA, Helmy NA, Radi AM. Neuromodulatory effect of cinnamon oil on behavioural disturbance, CYP1A1, iNOStranscripts and neurochemical alterations induced by deltamethrin in rat brain. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2021; 209:111820. [PMID: 33385678 DOI: 10.1016/j.ecoenv.2020.111820] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 12/10/2020] [Accepted: 12/16/2020] [Indexed: 06/12/2023]
Abstract
The objective of this study was to investigate the influence of deltamethrin (DLM)on brain function and to find whether DLM-induced neurotoxicity is prevented by the treatment with cinnamon oil. Four groups of ten Wistar albino male rats each were used. Group I (control) received saline only. Group II received cinnamon oil alone at 0.5 mg/kg B.W. intraperitonally, whereas Group III received orally DLM alone at 6 mg/kg B.W. Groups IV was treated with cinnamon oil plus DLM for 21 days to induce neurotoxicity. Rat behaviour, brain acetylcholine esterase (AChE), serotonin, oxidative stress profile were assessed. Serum sampling for the assessment of corticosterone concentration was also carried out. Finally, we demonstrate the gene expression of CYP1A1 and iNOS and the histological picture of the brain. Considering the behaviour assessment, DLM administration alone caused neurobehavioral deficits manifested by anxiety-like behavior which represented ina marked decrease in the sleeping frequency and duration, and marked increase the digging frequency and a wake non-active behavior duration. Moreover, the open field result showed a significant decrease in central square entries and duration. The neurochemical analysis revealed that DLM significantly suppressed AChE activity and elevated serotonin and corticosterone concentrations. Furthermore, results revealed thatthe brain reduced glutathione (GSH) content, superoxide dismutase (SOD) activity and malondialdehyde (MDA) concentration were significantly altered in DLM treated rats. Neurochemical disturbances were confirmed by histopathological changes in the brain. Furthermore, DLM up-regulates the mRNA expression of brain CYP1A1 and iNOS. Co-treatment with cinnamon oil exhibited significant improvement in behavioural performance and the brain antioxidant capacities with an increase in AChE activity and diminished the concentration of serotonin, serum corticosterone and MDA. Cinnamon oil treatment resulted in down-regulation of CYP1A1 and iNOS and improve the histologically picture. In conclusion, cinnamon oil ameliorated DLM-induced neurotoxicity through preventing oxidative stress-induced genotoxicity and apoptosis of brain in rats.
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Affiliation(s)
- Walaa M S Ahmed
- Department of Clinical Pathology, Faculty of Veterinary Medicine, Beni-Suef University, Beni-Suef 62511, Egypt
| | - Naglaa M Abdel-Azeem
- Department of Animal and Poultry Management and Wealth Development, Faculty of Veterinary Medicine,Beni-Suef University, Beni-Suef 62511, Egypt
| | - Marwa A Ibrahim
- Department of Biochemistry, Faculty of Veterinary Medicine, Cairo University, Giza Egypt
| | - Nermeen A Helmy
- Department of Physiology, Faculty of Veterinary Medicine, Beni-Suef University, Beni-Suef 62511, Egypt
| | - Abeer M Radi
- Department of Pharmacology, Faculty of Veterinary Medicine, Beni-Suef University, Beni-Suef 62511, Egypt
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Passantino A, Elwood RW, Coluccio P. Why Protect Decapod Crustaceans Used as Models in Biomedical Research and in Ecotoxicology? Ethical and Legislative Considerations. Animals (Basel) 2021; 11:ani11010073. [PMID: 33401555 PMCID: PMC7823715 DOI: 10.3390/ani11010073] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Revised: 12/23/2020] [Accepted: 12/29/2020] [Indexed: 12/26/2022] Open
Abstract
Simple Summary Current European legislation that protects animals used for scientific purposes excludes decapod crustaceans (for example, lobster, crab and crayfish) on the grounds that they are non-sentient and, therefore, incapable of suffering. However, recent work suggests that this view requires substantial revision. Our current understanding of the nervous systems and behavior of decapods suggests an urgent need to amend and update all relevant legislation. This paper examines recent experiments that suggest sentience and how that work has changed current opinion. It reflects on the use of decapods as models in biomedical research and in ecotoxicology, and it recommends that these animals should be included in the European protection legislation. Abstract Decapod crustaceans are widely used as experimental models, due to their biology, their sensitivity to pollutants and/or their convenience of collection and use. Decapods have been viewed as being non-sentient, and are not covered by current legislation from the European Parliament. However, recent studies suggest it is likely that they experience pain and may have the capacity to suffer. Accordingly, there is ethical concern regarding their continued use in research in the absence of protective measures. We argue that their welfare should be taken into account and included in ethical review processes that include the assessment of welfare and the minimization or alleviation of potential pain. We review the current use of these animals in research and the recent experiments that suggest sentience in this group. We also review recent changes in the views of scientists, veterinary scientists and animal charity groups, and their conclusion that these animals are likely to be sentient, and that changes in legislation are needed to protect them. A precautionary approach should be adopted to safeguard these animals from possible pain and suffering. Finally, we recommend that decapods be included in the European legislation concerning the welfare of animals used in experimentation.
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Affiliation(s)
- Annamaria Passantino
- Department of Veterinary Sciences, University of Messina-Polo Universitario Annunziata, 98168 Messina, Italy
- Correspondence:
| | - Robert William Elwood
- School of Biological Sciences, Queen’s University, Belfast BT9 5DL, Northern Ireland, UK;
| | - Paolo Coluccio
- Department of Neurosciences, Psychology, Drug Research and Child Health (NEUROFARBA), University of Florence, Viale Pieraccini 6, 50139 Firenze, Italy;
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Bacqué-Cazenave J, Bharatiya R, Barrière G, Delbecque JP, Bouguiyoud N, Di Giovanni G, Cattaert D, De Deurwaerdère P. Serotonin in Animal Cognition and Behavior. Int J Mol Sci 2020; 21:ijms21051649. [PMID: 32121267 PMCID: PMC7084567 DOI: 10.3390/ijms21051649] [Citation(s) in RCA: 151] [Impact Index Per Article: 37.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 02/25/2020] [Accepted: 02/25/2020] [Indexed: 12/20/2022] Open
Abstract
Serotonin (5-hydroxytryptamine, 5-HT) is acknowledged as a major neuromodulator of nervous systems in both invertebrates and vertebrates. It has been proposed for several decades that it impacts animal cognition and behavior. In spite of a completely distinct organization of the 5-HT systems across the animal kingdom, several lines of evidence suggest that the influences of 5-HT on behavior and cognition are evolutionary conserved. In this review, we have selected some behaviors classically evoked when addressing the roles of 5-HT on nervous system functions. In particular, we focus on the motor activity, arousal, sleep and circadian rhythm, feeding, social interactions and aggressiveness, anxiety, mood, learning and memory, or impulsive/compulsive dimension and behavioral flexibility. The roles of 5-HT, illustrated in both invertebrates and vertebrates, show that it is more able to potentiate or mitigate the neuronal responses necessary for the fine-tuning of most behaviors, rather than to trigger or halt a specific behavior. 5-HT is, therefore, the prototypical neuromodulator fundamentally involved in the adaptation of all organisms across the animal kingdom.
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Affiliation(s)
- Julien Bacqué-Cazenave
- INCIA, UMR5287, Centre National de la Recherche Scientifique, 33076 Bordeaux, France; (J.B.-C.); (R.B.); (G.B.); (J.-P.D.); (N.B.)
| | - Rahul Bharatiya
- INCIA, UMR5287, Centre National de la Recherche Scientifique, 33076 Bordeaux, France; (J.B.-C.); (R.B.); (G.B.); (J.-P.D.); (N.B.)
- Department of Biomedical Sciences, Section of Neuroscience and Clinical Pharmacology, University of Cagliari, 09100 Cagliari, Italy
| | - Grégory Barrière
- INCIA, UMR5287, Centre National de la Recherche Scientifique, 33076 Bordeaux, France; (J.B.-C.); (R.B.); (G.B.); (J.-P.D.); (N.B.)
| | - Jean-Paul Delbecque
- INCIA, UMR5287, Centre National de la Recherche Scientifique, 33076 Bordeaux, France; (J.B.-C.); (R.B.); (G.B.); (J.-P.D.); (N.B.)
| | - Nouhaila Bouguiyoud
- INCIA, UMR5287, Centre National de la Recherche Scientifique, 33076 Bordeaux, France; (J.B.-C.); (R.B.); (G.B.); (J.-P.D.); (N.B.)
| | - Giuseppe Di Giovanni
- Laboratory of Neurophysiology, Department of Physiology and Biochemistry, Faculty of Medicine and Surgery, University of Malta, MSD 2080 Msida, Malta;
- School of Biosciences, Neuroscience Division, Cardiff University, Cardiff CF24 4HQ, UK
| | - Daniel Cattaert
- INCIA, UMR5287, Centre National de la Recherche Scientifique, 33076 Bordeaux, France; (J.B.-C.); (R.B.); (G.B.); (J.-P.D.); (N.B.)
- Correspondence: (D.C.); (P.D.D.)
| | - Philippe De Deurwaerdère
- INCIA, UMR5287, Centre National de la Recherche Scientifique, 33076 Bordeaux, France; (J.B.-C.); (R.B.); (G.B.); (J.-P.D.); (N.B.)
- Correspondence: (D.C.); (P.D.D.)
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Abreu MS, Maximino C, Banha F, Anastácio PM, Demin KA, Kalueff AV, Soares MC. Emotional behavior in aquatic organisms? Lessons from crayfish and zebrafish. J Neurosci Res 2019; 98:764-779. [DOI: 10.1002/jnr.24550] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Revised: 09/24/2019] [Accepted: 10/15/2019] [Indexed: 12/17/2022]
Affiliation(s)
- Murilo S. Abreu
- Bioscience Institute University of Passo Fundo (UPF) Passo Fundo Brazil
- The International Zebrafish Neuroscience Research Consortium (ZNRC) Slidell LA USA
| | - Caio Maximino
- The International Zebrafish Neuroscience Research Consortium (ZNRC) Slidell LA USA
- Institute of Health and Biological Studies Federal University of Southern and Southeastern Pará, Unidade III Marabá Brazil
| | - Filipe Banha
- Department of Landscape, Environment and Planning MARE – Marine and Environmental Sciences Centre University of Évora Évora Portugal
| | - Pedro M. Anastácio
- Department of Landscape, Environment and Planning MARE – Marine and Environmental Sciences Centre University of Évora Évora Portugal
| | - Konstantin A. Demin
- Institute of Experimental Medicine Almazov National Medical Research Center Ministry of Healthcare of Russian Federation St. Petersburg Russia
- Institute of Translational Biomedicine St. Petersburg State University St. Petersburg Russia
| | - Allan V. Kalueff
- School of Pharmacy Southwest University Chongqing China
- Ural Federal University Ekaterinburg Russia
| | - Marta C. Soares
- CIBIO, Research Centre in Biodiversity and Genetic Resources University of Porto Porto Portugal
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Bacqué-Cazenave J, Fossat P, Issa FA, Edwards DH, Delbecque JP, Cattaert D. Duality of 5-HT Effects on Crayfish Motoneurons. Front Physiol 2019; 10:1280. [PMID: 31695619 PMCID: PMC6817598 DOI: 10.3389/fphys.2019.01280] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Accepted: 09/24/2019] [Indexed: 11/13/2022] Open
Abstract
Serotonin (5-HT) is a major neuromodulator acting on the nervous system. Its various effects have been studied in vertebrates, as well as in arthropods, from the cellular and subcellular compartments up to the behavioral level, which includes the control of mood, aggression, locomotion, and anxiety. The diversity of responses of neurons to 5-HT has been related to its mode of application, the diversity of 5-HT-receptors, and the animals’ social status history. In the locomotor network of socially isolated crayfish, the duality of 5-HT-evoked responses (excitatory/inhibitory) on motoneurons (MNs), sensorimotor pathways, and their consequences on motor network activity has largely been studied. The aim of the present report is to examine if this duality of exogenous 5-HT-evoked responses in the crayfish locomotor network can be reproduced by direct activation of 5-HT neurons in the case of socially isolated animals. Our previous studies have focused on the mechanisms supporting these opposite effects on MNs, pointing out spatial segregation of 5-HT receptors responsible either for positive or negative responses. Here, we report new findings indicating that excitatory and inhibitory effects can be achieved simultaneously in different leg MNs by the activation of a single 5-HT cell in the first abdominal ganglion.
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Affiliation(s)
- Julien Bacqué-Cazenave
- University of Bordeaux, CNRS, Institut de Neurosciences Cognitives et Intégratives d'Aquitaine (INCIA) UMR5287, Bordeaux, France
| | - Pascal Fossat
- University of Bordeaux, CNRS, Institut de Neurosciences Cognitives et Intégratives d'Aquitaine (INCIA) UMR5287, Bordeaux, France
| | - Fadi A Issa
- Neuroscience Institute, College of Arts and Sciences, Georgia State University, Atlanta, GA, United States
| | - Donald H Edwards
- Neuroscience Institute, College of Arts and Sciences, Georgia State University, Atlanta, GA, United States
| | - Jean Paul Delbecque
- University of Bordeaux, CNRS, Institut de Neurosciences Cognitives et Intégratives d'Aquitaine (INCIA) UMR5287, Bordeaux, France
| | - Daniel Cattaert
- University of Bordeaux, CNRS, Institut de Neurosciences Cognitives et Intégratives d'Aquitaine (INCIA) UMR5287, Bordeaux, France
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Elwood RW. Discrimination between nociceptive reflexes and more complex responses consistent with pain in crustaceans. Philos Trans R Soc Lond B Biol Sci 2019; 374:20190368. [PMID: 31544604 DOI: 10.1098/rstb.2019.0368] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Animals have quick-acting nociceptive reflexes that protect them from tissue damage. Some taxa have also evolved the capacity for pain. Pain appears to be linked to long-term changes in motivation brought about by the aversive nature of the experience. Pain presumably enhances long-term protection through behaviour modification based, in part, on memory. However, crustaceans have long been viewed as responding purely by reflex and thus not experiencing pain. This paper considers behavioural and physiological criteria that distinguish nociception from potential pain in this taxon. These include trade-offs with other motivational systems and prolonged motivational change. Complex, prolonged grooming or rubbing demonstrate the perception of the specific site of stimulus application. Recent evidence of fitness-enhancing, anxiety-like states is also consistent with the idea of pain. Physiological changes in response to noxious stimuli mediate some of the behavioural change. Rapid avoidance learning and prolonged memory indicate central processing rather than mere reflexes. Thus, available data go beyond the idea of just nociception. However, the impossibility of total proof of pain described in ways appropriate for our own species means that pain in crustaceans is still disputed. Pain in animals should be defined in ways that do not depend on human pain experience. This article is part of the Theo Murphy meeting issue 'Evolution of mechanisms and behaviour important for pain'.
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Affiliation(s)
- Robert W Elwood
- School of Biological Sciences, Queen's University, Belfast BT9 7BL, UK
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19
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Identification of putative amine receptor complement in the eyestalk of the crayfish, Procambarus clarkii. INVERTEBRATE NEUROSCIENCE 2019; 19:12. [PMID: 31549228 DOI: 10.1007/s10158-019-0232-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Accepted: 09/16/2019] [Indexed: 10/25/2022]
Abstract
In decapod crustaceans, the amines dopamine, octopamine, serotonin, and histamine are known to serve as locally released and/or circulating neuromodulators. While many studies have focused on determining the modulatory actions of amines on decapod nervous systems, comparatively little is known about the identity of the receptors through which they exert their actions. Here, a crayfish, Procambarus clarkii, tissue-specific transcriptome was used to identify putative amine receptors in the eyestalk, a structure composed largely of the eyestalk ganglia, including the neuroendocrine X-organ-sinus gland system, and retina. Transcripts encoding 17 distinct putative amine receptors, three dopamine (one dopamine 1-like, one dopamine 2-like, and one dopamine/ecdysteroid-like), five octopamine (one alpha-like, three beta-like, and one octopamine/tyramine-like), three serotonin (two type-1-like and one type-7-like), and six histamine (five histamine-gated chloride channel A-like and one histamine-gated chloride channel B-like) were identified in the assembly. Comparison of the nucleotide sequence of the transcript encoding one predicted type-1-like serotonin receptor with that cloned previously from the P. clarkii nervous system shows the two sequences to be essentially identical, providing increased support for the validity of the transcripts used to deduce the proteins reported here. Reciprocal BLAST and structural/functional domain analyses support the protein family annotations ascribed to the putative P. clarkii receptors. These data represent the first large-scale description of amine receptors from P. clarkii, and as such provide a new resource for initiating gene-based studies of aminergic control of physiology/behavior at the level of receptors in this species.
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Bacqué-Cazenave J, Berthomieu M, Cattaert D, Fossat P, Delbecque JP. Do arthropods feel anxious during molts? ACTA ACUST UNITED AC 2019; 222:jeb.186999. [PMID: 30530836 DOI: 10.1242/jeb.186999] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Accepted: 11/30/2018] [Indexed: 11/20/2022]
Abstract
The molting process of arthropods, chiefly controlled by ecdysteroids, is generally considered very stressful. Our previous investigations have shown that crayfish, after having experienced stressful situations, display anxiety-like behavior (ALB), characterized by aversion to light in a dark/light plus-maze (DLPM). In the present experiments, the spontaneous exploratory behavior of isolated crayfish was analyzed in a DLPM at different stages of their molt cycle. All tested animals displayed transitory aversion to light similar to ALB, before and, mostly, after molting, but not during inter-molt. Injection of ecdysteroids into inter-molt animals elicited ALB after a delay of 4 days, suggesting a long-term, possibly indirect, hormonal effect. Importantly, ecdysteroid-induced ALB was suppressed by the injection of an anxiolytic benzodiazepine. Thus, molts and their hormonal control impose internal stress on crayfish, leading to aversion behavior that has the main characteristics of anxiety. These observations are possibly generalizable to many other arthropods.
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Affiliation(s)
- Julien Bacqué-Cazenave
- Department of Life and Health Science, Université de Bordeaux. CNRS, UMR5287, INCIA (Institut des Neurosciences Cognitives et Intégratives d'Aquitaine), 146 Rue Léo Saignat, 33076 Bordeaux, France
| | - Marion Berthomieu
- Department of Life and Health Science, Université de Bordeaux. CNRS, UMR5287, INCIA (Institut des Neurosciences Cognitives et Intégratives d'Aquitaine), 146 Rue Léo Saignat, 33076 Bordeaux, France
| | - Daniel Cattaert
- Department of Life and Health Science, Université de Bordeaux. CNRS, UMR5287, INCIA (Institut des Neurosciences Cognitives et Intégratives d'Aquitaine), 146 Rue Léo Saignat, 33076 Bordeaux, France
| | - Pascal Fossat
- Department of Life and Health Science, Université de Bordeaux. CNRS, UMR5287, INCIA (Institut des Neurosciences Cognitives et Intégratives d'Aquitaine), 146 Rue Léo Saignat, 33076 Bordeaux, France
| | - Jean Paul Delbecque
- Department of Life and Health Science, Université de Bordeaux. CNRS, UMR5287, INCIA (Institut des Neurosciences Cognitives et Intégratives d'Aquitaine), 146 Rue Léo Saignat, 33076 Bordeaux, France
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22
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23
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Yang X, Huang G, Xu M, Zhang C, Cheng Y. Molecular cloning and functional expression of the 5-HT 7 receptor in Chinese mitten crab (Eriocheir sinensis). Comp Biochem Physiol B Biochem Mol Biol 2018; 226:10-17. [PMID: 30110659 DOI: 10.1016/j.cbpb.2018.07.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2018] [Revised: 07/23/2018] [Accepted: 07/30/2018] [Indexed: 11/18/2022]
Abstract
Serotonin (5-HT) regulates numerous physiological functions and processes, such as light adaptation, food intake and ovarian maturation, and plays the role through 5-HT receptors. To our knowledge, this is the first study to isolate and characterize the serotonin receptor 7 (5-HT7 receptor) cDNA encoded in Eriocheir sinensis, an economically important aquaculture species in China, by performing rapid-amplification of cDNA ends. The full-length of 5-HT7 receptor gene cDNA is 2328 bp and encodes a polypeptide with 590 amino acids that are highly homologous with other crustaceans 5-HT7 receptor genes. Analysis of the deduced amino acid sequence of the 5-HT7, including 7 transmembrane domains and some common features of G protein-coupled receptors (GPCRs), indicated that 5-HT7 receptor was a member of GPCRs family. A gene expression analysis of the 5-HT7 receptor by RT-PCR revealed that the 5-HT7 receptor transcripts were widely distributed in various tissues, in which high expression levels were observed in the cranial ganglia, thoracic ganglia and intestines. Further study about the effects of photoperiods on the 5-HT7 expression in the tissues showed that a significantly increasing expression of the 5-HT7 receptor was observed in the thoracic ganglia induced by constant light. In addition, in the eyestalks, the expression levels of 5-HT7 mRNA in constant darkness and constant light were lower than control treatment. Then, the expression levels of the 5-HT7 receptor in three feeding statuses displayed that there were significantly increasing expressions in the hepatopancreas and intestines after feeding, compared with before feeding and during the feeding period. Finally, the 5-HT7 mRNA expression levels in stage III and stage IV were higher than the levels in stage I of ovarian development. Our experimental results showed that the 5-HT7 receptor structurally belongs to GPCRs, and the thoracic ganglia and eyestalks are the important tissues of the 5-HT7 receptor for light adaptation. The 5-HT7 receptor may also be involved in the physiological regulation of the hepatopancreas and intestines after ingestion in E. sinensis. In addition, the 5-HT7 receptor is involved in the process of ovarian maturation. The study provided a foundation for further research of light adaptation, digestive functions and ovarian maturation of the 5-HT7 receptor in Decapoda.
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Affiliation(s)
- Xiaozhen Yang
- National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai, China; Key Laboratory of Freshwater Aquatic Genetic Resources, Ministry of Agriculture, Shanghai Ocean University, Shanghai, China; Shanghai Engineering Research Center of Aquaculture, Shanghai Ocean University, Shanghai, China
| | - Genyong Huang
- National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai, China; Key Laboratory of Freshwater Aquatic Genetic Resources, Ministry of Agriculture, Shanghai Ocean University, Shanghai, China; Shanghai Engineering Research Center of Aquaculture, Shanghai Ocean University, Shanghai, China
| | - Minjie Xu
- National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai, China; Key Laboratory of Freshwater Aquatic Genetic Resources, Ministry of Agriculture, Shanghai Ocean University, Shanghai, China; Shanghai Engineering Research Center of Aquaculture, Shanghai Ocean University, Shanghai, China
| | - Cong Zhang
- National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai, China; Key Laboratory of Freshwater Aquatic Genetic Resources, Ministry of Agriculture, Shanghai Ocean University, Shanghai, China; Shanghai Engineering Research Center of Aquaculture, Shanghai Ocean University, Shanghai, China
| | - Yongxu Cheng
- National Demonstration Center for Experimental Fisheries Science Education, Shanghai Ocean University, Shanghai, China; Key Laboratory of Freshwater Aquatic Genetic Resources, Ministry of Agriculture, Shanghai Ocean University, Shanghai, China; Shanghai Engineering Research Center of Aquaculture, Shanghai Ocean University, Shanghai, China.
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Bacqué-Cazenave J, Cattaert D, Delbecque JP, Fossat P. Serotonin has opposite effects on the aggressiveness of crayfish, facing either a smaller or a larger rival: alteration of size perception. J Exp Biol 2018; 221:jeb.177840. [DOI: 10.1242/jeb.177840] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Accepted: 04/23/2018] [Indexed: 12/27/2022]
Abstract
We injected serotonin (5-HT) in adult male crayfish before pairing them with size-matched non-injected competitors, and we observed dyadic agonistic interactions. Paradoxically, 5-HT elicited opposite behavioral responses if the injected animal was opposed by a smaller or larger rival: the level of aggressiveness of the injected crayfish was higher in front of a larger rival but lower in front of a smaller rival. Our results indicate that the effects of 5-HT on aggressiveness are dependent on the perception of the relative size difference of the opponent. In both cases, however, 5-HT significantly delayed the decision to retreat. We conclude that 5-HT does not primarily act on aggressiveness but rather on the brain centers that integrate risk assessment and/or decision-making, which then modulate the aggressive response. Our study supports a reinterpretation of the role of 5-HT in crustacean agonistic behavior that may be of interest for other animals.
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Affiliation(s)
- Julien Bacqué-Cazenave
- Université de Bordeaux. CNRS, UMR5287, INCIA (Institut des Neurosciences Cognitives et Intégratives d'Aquitaine), 146 Rue Leo Saignat, 33076 Bordeaux, France
| | - Daniel Cattaert
- Université de Bordeaux. CNRS, UMR5287, INCIA (Institut des Neurosciences Cognitives et Intégratives d'Aquitaine), 146 Rue Leo Saignat, 33076 Bordeaux, France
| | - Jean Paul Delbecque
- Université de Bordeaux. CNRS, UMR5287, INCIA (Institut des Neurosciences Cognitives et Intégratives d'Aquitaine), 146 Rue Leo Saignat, 33076 Bordeaux, France
| | - Pascal Fossat
- Université de Bordeaux. CNRS, UMR5287, INCIA (Institut des Neurosciences Cognitives et Intégratives d'Aquitaine), 146 Rue Leo Saignat, 33076 Bordeaux, France
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Perrot-Minnot MJ, Banchetry L, Cézilly F. Anxiety-like behaviour increases safety from fish predation in an amphipod crustacea. ROYAL SOCIETY OPEN SCIENCE 2017; 4:171558. [PMID: 29308271 PMCID: PMC5750038 DOI: 10.1098/rsos.171558] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Accepted: 11/07/2017] [Indexed: 06/07/2023]
Abstract
Anxiety is an emotional state generally expressed as sustained apprehension of the environment and elevated vigilance. It has been widely reported in vertebrates and, more recently, in a few invertebrate species. However, its fitness value remains elusive. We investigated anxiety-like behaviour and its consequences in an amphipod crustacean, using electric shock as aversive stimuli, and pharmacological assays. An anxiety-like state induced by electric shocks in Gammarus fossarum was expressed through increased sheltering behaviour in the absence of predation risk, thereby showing the pervasive nature of such behavioural response. Increasing the number of electric shocks both increased refuge use and delayed behavioural recovery. The behavioural effect of electric shock was mitigated by pre-treatment with LY354740, a metabotropic glutamate receptor group II/III agonist. Importantly, we found that this modulation of decision-making under an anxiety-like state resulted in an increased survival to predation in microcosm experiments. This study confirms the interest in taking an evolutionary view to the study of anxiety and calls for further investigation on the costs counterbalancing the survival benefit of an elevated anxiety level evidenced here.
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Ooi FK, Prahlad V. Olfactory experience primes the heat shock transcription factor HSF-1 to enhance the expression of molecular chaperones in C. elegans. Sci Signal 2017; 10:10/501/eaan4893. [PMID: 29042483 DOI: 10.1126/scisignal.aan4893] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Learning, a process by which animals modify their behavior as a result of experience, enables organisms to synthesize information from their surroundings to acquire resources and avoid danger. We showed that a previous encounter with only the odor of pathogenic bacteria prepared Caenorhabditis elegans to survive exposure to the pathogen by increasing the heat shock factor 1 (HSF-1)-dependent expression of genes encoding molecular chaperones. Experience-mediated enhancement of chaperone gene expression required serotonin, which primed HSF-1 to enhance the expression of molecular chaperone genes by promoting its localization to RNA polymerase II-enriched nuclear loci, even before transcription occurred. However, HSF-1-dependent chaperone gene expression was stimulated only if and when animals encountered the pathogen. Thus, learning equips C. elegans to better survive environmental dangers by preemptively and specifically initiating transcriptional mechanisms throughout the whole organism that prepare the animal to respond rapidly to proteotoxic agents. These studies provide one plausible basis for the protective role of environmental enrichment in disease.
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Affiliation(s)
- Felicia K Ooi
- Department of Biology, Aging Mind and Brain Initiative, 143 Biology Building East, 338 BBE, University of Iowa, Iowa City, IA 52242, USA
| | - Veena Prahlad
- Department of Biology, Aging Mind and Brain Initiative, 143 Biology Building East, 338 BBE, University of Iowa, Iowa City, IA 52242, USA.
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27
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Blewett TA, Newton D, Flynn SL, Alessi DS, Goss GG, Hamilton TJ. Cadmium bioaccumulates after acute exposure but has no effect on locomotion or shelter-seeking behaviour in the invasive green shore crab ( Carcinus maenas). CONSERVATION PHYSIOLOGY 2017; 5:cox057. [PMID: 28979787 PMCID: PMC5620452 DOI: 10.1093/conphys/cox057] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Revised: 08/10/2017] [Accepted: 09/12/2017] [Indexed: 06/07/2023]
Abstract
Cadmium (Cd2+) is a non-essential metal ubiquitous in the environment due to industrial processes. However, little is known regarding the ability of Cd2+ to impact the behaviour of aquatic animals in receiving environments. Green shore crabs (Carcinus maenas) were exposed to waterborne Cd2+ [control (no Cd2+), low (0.30 μmol/L), medium (3.3 μmol/L) and high (63 μmol/L)], for 24 h, then, crabs were placed in an open field and shelter test to determine potential changes in locomotion and preference for shelter. Tissues (gill, haemolymph, stomatogastric ganglion) were taken for bioaccumulation analysis of Cd2+ and ion content. Behavioural testing was recorded with a motion-tracking software system and showed no impact of Cd2+ on any variable in either of the tests used. All three tissues accumulated Cd2+ in a concentration-dependent manner. Crabs exposed to low Cd2+ showed a small but significant decrease in haemolymph Ca2+, however, this effect was not present at higher Cd2+ exposures. Overall, the results indicate that short-term Cd2+ exposure, and the resulting Cd2+ accumulation, had no effect on locomotor and anxiety-related behaviour of green shore crabs.
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Affiliation(s)
- Tamzin A Blewett
- Department of Biological Science, University of Alberta, Edmonton, Alberta, Canada
| | - Dustin Newton
- Department of Psychology, MacEwan University, Edmonton, Alberta, Canada
| | - Shannon L Flynn
- Department of Biological Science, University of Alberta, Edmonton, Alberta, Canada
- Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, Alberta, Canada
- School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Daniel S Alessi
- Department of Biological Science, University of Alberta, Edmonton, Alberta, Canada
- Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Greg G Goss
- Department of Biological Science, University of Alberta, Edmonton, Alberta, Canada
| | - Trevor J Hamilton
- Department of Psychology, MacEwan University, Edmonton, Alberta, Canada
- Neuroscience and Mental Health Institute, University of Alberta, Edmonton,Alberta, Canada
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28
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Mitchell MD, Bairos-Novak KR, Ferrari MCO. Mechanisms underlying the control of responses to predator odours in aquatic prey. J Exp Biol 2017; 220:1937-1946. [DOI: 10.1242/jeb.135137] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
ABSTRACT
In aquatic systems, chemical cues are a major source of information through which animals are able to assess the current state of their environment to gain information about local predation risk. Prey use chemicals released by predators (including cues from a predator's diet) and other prey (such as alarm cues and disturbance cues) to mediate a range of behavioural, morphological and life-history antipredator defences. Despite the wealth of knowledge on the ecology of antipredator defences, we know surprisingly little about the physiological mechanisms that control the expression of these defensive traits. Here, we summarise the current literature on the mechanisms known to specifically mediate responses to predator odours, including dietary cues. Interestingly, these studies suggest that independent pathways may control predator-specific responses, highlighting the need for greater focus on predator-derived cues when looking at the mechanistic control of responses. Thus, we urge researchers to tease apart the effects of predator-specific cues (i.e. chemicals representing a predator's identity) from those of diet-mediated cues (i.e. chemicals released from a predator's diet), which are known to mediate different ecological endpoints. Finally, we suggest some key areas of research that would greatly benefit from a more mechanistic approach.
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Affiliation(s)
- Matthew D. Mitchell
- Department of Biomedical Sciences, WCVM, University of Saskatchewan, Saskatoon, SK, Canada S7N 5B4
| | | | - Maud C. O. Ferrari
- Department of Biomedical Sciences, WCVM, University of Saskatchewan, Saskatoon, SK, Canada S7N 5B4
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29
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Aversive responses by shore crabs to acetic acid but not to capsaicin. Behav Processes 2017; 140:1-5. [PMID: 28365460 DOI: 10.1016/j.beproc.2017.03.022] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2016] [Revised: 03/27/2017] [Accepted: 03/28/2017] [Indexed: 01/24/2023]
Abstract
Nociception is the ability to encode and perceive harmful stimuli and allows for a rapid reflexive withdrawal. In some species, nociception might be accompanied by a pain experience, which is a negative feeling that allows for longer-term changes in behaviour. Different types of stimuli may affect nociceptors, but in crustaceans there is conflicting evidence about the ability to respond to chemical stimuli. This study attempts to resolve this situation by testing behavioural responses of the common shore crab, Carcinus maenas, to two chemical irritants frequently used in vertebrate pain studies (acetic acid and capsaicin). In our first experiment acetic acid, water, capsaicin or mineral oil were applied by brush to the mouth, and in a second experiment treatments were applied to the eyes. Application of acetic acid had a marked effect on behaviour that included vigorous movement of mouth parts, scratching at the mouth with the claws and attempts to escape from the enclosure. Acetic acid also caused holding down of the acid-treated eye in the socket. By contrast, capsaicin had no effect and was no different to the control treatment of mineral oil and water. These results demonstrate responsiveness to acetic acid and thus nociceptive capacity for at least some chemicals. Further, the responses that persist after application were consistent with the idea of pain, however, proof of pain is not possible in any animal.
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30
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Bacqué-Cazenave J, Cattaert D, Delbecque JP, Fossat P. Social harassment induces anxiety-like behaviour in crayfish. Sci Rep 2017; 7:39935. [PMID: 28045136 PMCID: PMC5206779 DOI: 10.1038/srep39935] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Accepted: 11/28/2016] [Indexed: 01/30/2023] Open
Abstract
Social interactions leading to dominance hierarchies often elicit psychological disorders in mammals including harassment and anxiety. Here, we demonstrate that this sequence also occurs in an invertebrate, the crayfish Procambarus clarkii. When placed in the restricted space of an aquarium, crayfish dyads generally fight until one of the opponents suddenly escapes, thereafter clearly expressing a submissive behaviour. Nevertheless, the winner frequently keeps on displaying excessive aggressive acts, having deleterious consequences in losers and interpreted as harassment behaviour. We indeed observed that, contrary to winners, losers expressed anxiety-like behaviour (ALB) in correlation with the stress intensity they suffered during the harassment period mainly. Injections of an anxiolytic abolished ALB, confirming its homology with anxiety. A serotonin (5-HT) antagonist had the same effect, suggesting a role for 5-HT, whose brain concentrations increased much more in losers than in winners. Our findings suggest that the bases of harassment and of its anxiogenic consequences have emerged very early during evolution, and emphasize crayfish as an unexpected but potentially fruitful model for the study of these social disorders.
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Affiliation(s)
- Julien Bacqué-Cazenave
- INCIA - Institut de Neurosciences Cognitives et Intégratives d'Aquitaine, University of Bordeaux, CNRS UMR 5287, 146 Rue Leo Saignat, 33076 Bordeaux, France
| | - Daniel Cattaert
- INCIA - Institut de Neurosciences Cognitives et Intégratives d'Aquitaine, University of Bordeaux, CNRS UMR 5287, 146 Rue Leo Saignat, 33076 Bordeaux, France
| | - Jean-Paul Delbecque
- INCIA - Institut de Neurosciences Cognitives et Intégratives d'Aquitaine, University of Bordeaux, CNRS UMR 5287, 146 Rue Leo Saignat, 33076 Bordeaux, France
| | - Pascal Fossat
- INCIA - Institut de Neurosciences Cognitives et Intégratives d'Aquitaine, University of Bordeaux, CNRS UMR 5287, 146 Rue Leo Saignat, 33076 Bordeaux, France
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31
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Elwood RW, Adams L. Electric shock causes physiological stress responses in shore crabs, consistent with prediction of pain. Biol Lett 2016; 11:rsbl.2015.0800. [PMID: 26559514 DOI: 10.1098/rsbl.2015.0800] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Animal pain is defined by a series of expectations or criteria, one of which is that there should be a physiological stress response associated with noxious stimuli. While crustacean stress responses have been demonstrated they are typically preceded by escape behaviour and thus the physiological change might be attributed to the behaviour rather than a pain experience. We found higher levels of stress as measured by lactate in shore crabs exposed to brief electric shock than non-shocked controls. However, shocked crabs showed more vigorous behaviour than controls. We then matched crabs with the same level of behaviour and still found that shocked crabs had stronger stress response compared with controls. The finding of the stress response, coupled with previous findings of long-term motivational change and avoidance learning, fulfils the criteria expected of a pain experience.
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Affiliation(s)
- Robert W Elwood
- School of Biological Sciences, Queen's University, Belfast BT9 7BL, UK
| | - Laura Adams
- School of Biological Sciences, Queen's University, Belfast BT9 7BL, UK
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32
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Elwood RW. Stress was never said to be pain: response to Stevens et al. (2016). Biol Lett 2016; 12:rsbl.2016.0126. [PMID: 27048469 DOI: 10.1098/rsbl.2016.0126] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2016] [Accepted: 03/09/2016] [Indexed: 11/12/2022] Open
Affiliation(s)
- Robert W Elwood
- School of Biological Sciences, Queen's University, Belfast BT9 7BL, UK
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33
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Magee B, Elwood RW. No discrimination shock avoidance with sequential presentation of stimuli but shore crabs still reduce shock exposure. Biol Open 2016; 5:883-8. [PMID: 27305928 PMCID: PMC4958278 DOI: 10.1242/bio.019216] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Insights into the potential for pain may be obtained from examination of behavioural responses to noxious stimuli. In particular, prolonged responses coupled with long-term motivational change and avoidance learning cannot be explained by nociceptive reflex but are consistent with the idea of pain. Here, we placed shore crabs alternately in two halves of a test area divided by an opaque partition. Each area had a dark shelter and in one repeated small electric shocks were delivered in an experimental but not in a control group. Crabs showed no specific avoidance of the shock shelter either during these trials or in a subsequent test in which both were offered simultaneously; however they often emerged from the shock shelter during a trial and thus avoided further shock. More crabs emerged in later trials and took less time to emerge than in early trials. Thus, despite the lack of discrimination learning between the two shelters they used other tactics to markedly reduce the amount of shock received. We note that a previous experiment using simultaneous presentation of two shelters demonstrated rapid discrimination and avoidance learning but the paradigm of sequential presentation appears to prevent this. Nevertheless, the data show clearly that the shock is aversive and tactics, other than discrimination learning, are used to avoid it. Thus, the behaviour is only partially consistent with the idea of pain. Summary: There was no discrimination shock avoidance with sequential presentation of stimuli but, consistent with pain, shore crabs used other tactics to reduce shock exposure.
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Affiliation(s)
- Barry Magee
- School of Biological Sciences, Queen's University, Belfast BT9 7BL, Northern Ireland, UK
| | - Robert W Elwood
- School of Biological Sciences, Queen's University, Belfast BT9 7BL, Northern Ireland, UK
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34
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Magee B, Elwood RW. Trade-offs between predator avoidance and electric shock avoidance in hermit crabs demonstrate a non-reflexive response to noxious stimuli consistent with prediction of pain. Behav Processes 2016; 130:31-5. [PMID: 27374025 DOI: 10.1016/j.beproc.2016.06.017] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2016] [Revised: 05/31/2016] [Accepted: 06/30/2016] [Indexed: 01/09/2023]
Abstract
Arthropods have long been thought to respond to noxious stimuli by reflex reaction. One way of testing if this is true is to provide the animal with a way to avoid the stimulus but to vary the potential cost of avoidance. If avoidance varies with potential cost then a decision making process is evident and the behaviour is not a mere reflex. Here we examine the responses of hermit crabs to electric shock within their shell when also exposed to predator or non-predator odours or to no odour. The electric shocks start with low voltage but increase in voltage with each repetition to determine how odour affects the voltage at which the shell is abandoned. There was no treatment effect on the voltage at which hermit crabs left their shells, however, those exposed to predator odours were less likely to evacuate their shells compared with no odour or low concentrations of non-predator odour. However, highly concentrated non-predator also inhibited evacuation. The data show that these crabs trade-off avoidance of electric shock with predator avoidance. They are thus not responding purely by reflex and the data are thus consistent with predictions of pain but do not prove pain.
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Affiliation(s)
- Barry Magee
- School of Biological Sciences, Queen's University Belfast, Belfast BT9 7BL, UK
| | - Robert W Elwood
- School of Biological Sciences, Queen's University Belfast, Belfast BT9 7BL, UK.
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35
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Acute fluoxetine exposure alters crab anxiety-like behaviour, but not aggressiveness. Sci Rep 2016; 6:19850. [PMID: 26806870 PMCID: PMC4726416 DOI: 10.1038/srep19850] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2015] [Accepted: 12/18/2015] [Indexed: 12/16/2022] Open
Abstract
Aggression and responsiveness to noxious stimuli are adaptable traits that are ubiquitous throughout the animal kingdom. Like vertebrate animals, some invertebrates have been shown to exhibit anxiety-like behaviour and altered levels of aggression that are modulated by the neurotransmitter serotonin. To investigate whether this influence of serotonin is conserved in crabs and whether these behaviours are sensitive to human antidepressant drugs; the striped shore crab, Pachygrapsus crassipes, was studied using anxiety (light/dark test) and aggression (mirror test) paradigms. Crabs were individually exposed to acute doses of the selective serotonin reuptake inhibitor, fluoxetine (5 or 25 mg/L), commonly known as Prozac®, followed by behavioural testing. The high dose of fluoxetine significantly decreased anxiety-like behaviour but had no impact on mobility or aggression. These results suggest that anxiety-like behaviour is more sensitive to modulation of serotonin than is aggressiveness in the shore crab.
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36
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Di Giovanni G, De Deurwaerdère P. New therapeutic opportunities for 5-HT2C receptor ligands in neuropsychiatric disorders. Pharmacol Ther 2015; 157:125-62. [PMID: 26617215 DOI: 10.1016/j.pharmthera.2015.11.009] [Citation(s) in RCA: 84] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The 5-HT2C receptor (R) displays a widespread distribution in the CNS and is involved in the action of 5-HT in all brain areas. Knowledge of its functional role in the CNS pathophysiology has been impaired for many years due to the lack of drugs capable of discriminating among 5-HT2R subtypes, and to a lesser extent to the 5-HT1B, 5-HT5, 5-HT6 and 5-HT7Rs. The situation has changed since the mid-90s due to the increased availability of new and selective synthesized compounds, the creation of 5-HT2C knock out mice, and the progress made in molecular biology. Many pharmacological classes of drugs including antipsychotics, antidepressants and anxiolytics display affinities toward 5-HT2CRs and new 5-HT2C ligands have been developed for various neuropsychiatric disorders. The 5-HT2CR is presumed to mediate tonic/constitutive and phasic controls on the activity of different central neurobiological networks. Preclinical data illustrate this complexity to a point that pharmaceutical companies developed either agonists or antagonists for the same disease. In order to better comprehend this complexity, this review will briefly describe the molecular pharmacology of 5-HT2CRs, as well as their cellular impacts in general, before addressing its central distribution in the mammalian brain. Thereafter, we review the preclinical efficacy of 5-HT2C ligands in numerous behavioral tests modeling human diseases, highlighting the multiple and competing actions of the 5-HT2CRs in neurobiological networks and monoaminergic systems. Notably, we will focus this evidence in the context of the physiopathology of psychiatric and neurological disorders including Parkinson's disease, levodopa-induced dyskinesia, and epilepsy.
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Affiliation(s)
- Giuseppe Di Giovanni
- Department of Physiology & Biochemistry, Faculty of Medicine and Surgery, University of Malta; Neuroscience Division, School of Biosciences, Cardiff University, Cardiff, UK.
| | - Philippe De Deurwaerdère
- Centre National de la Recherche Scientifique (Unité Mixte de Recherche 5293) 33076 Bordeaux Cedex, France.
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