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Brown JW, Berg OH, Boutko A, Stoerck C, Boersma MA, Frost WN. Division of labor for defensive retaliation and preemption by the peripheral and central nervous systems in the nudibranch Berghia. Curr Biol 2024; 34:2175-2185.e4. [PMID: 38718797 DOI: 10.1016/j.cub.2024.04.038] [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: 07/26/2023] [Revised: 01/02/2024] [Accepted: 04/15/2024] [Indexed: 05/23/2024]
Abstract
Relatively little is known about how peripheral nervous systems (PNSs) contribute to the patterning of behavior in which their role transcends the simple execution of central motor commands or mediation of reflexes. We sought to draw inferences to this end in the aeolid nudibranch Berghia stephanieae, which generates a rapid, dramatic defense behavior, "bristling." This behavior involves the coordinated movement of cerata, dozens of venomous appendages emerging from the animal's mantle. Our investigations revealed that bristling constitutes a stereotyped but non-reflexive two-stage behavior: an initial adduction of proximate cerata to sting the offending stimulus (stage 1) followed by a coordinated radial extension of remaining cerata to create a pincushion-like defensive screen around the animal (stage 2). In decerebrated specimens, stage 1 bristling was preserved, while stage 2 bristling was replaced by slower, uncoordinated ceratal movements. We conclude from these observations that, first, the animal's PNS and central nervous system (CNS) mediate stages 1 and 2 of bristling, respectively; second, the behavior propagates through the body utilizing both peripheral- and central-origin nerve networks that support different signaling kinetics; and third, the former network inhibits the latter in the body region being stimulated. These findings extend our understanding of the PNS' computational capacity and provide insight into a neuroethological scheme in which the CNS and PNS both independently and interactively pattern different aspects of non-reflexive behavior.
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Affiliation(s)
- Jeffrey W Brown
- Stanson Toshok Center for Brain Function and Repair, Rosalind Franklin University of Medicine and Science, North Chicago, IL 60064, USA; School of Graduate and Postdoctoral Studies, Rosalind Franklin University of Medicine and Science, North Chicago, IL 60064, USA
| | - Ondine H Berg
- Neuroscience Program, Lake Forest College, Lake Forest, IL 60045, USA
| | - Anastasiya Boutko
- The Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, IL 60064, USA
| | - Cody Stoerck
- Department of Psychology, California State University at Fullerton, Fullerton, CA 92831, USA
| | | | - William N Frost
- Stanson Toshok Center for Brain Function and Repair, Rosalind Franklin University of Medicine and Science, North Chicago, IL 60064, USA; School of Graduate and Postdoctoral Studies, Rosalind Franklin University of Medicine and Science, North Chicago, IL 60064, USA; The Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, IL 60064, USA.
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2
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Norekian T, Liu Y, Gribkova ED, Cui J, Gillette R. A peripheral subepithelial network for chemotactile processing in the predatory sea slug Pleurobranchaea californica. PLoS One 2024; 19:e0296872. [PMID: 38329975 PMCID: PMC10852322 DOI: 10.1371/journal.pone.0296872] [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: 05/30/2023] [Accepted: 12/20/2023] [Indexed: 02/10/2024] Open
Abstract
Many soft-bodied animals have extensive peripheral nervous systems (PNS) with significant sensory roles. One such, the sea slug Pleurobranchaea californica, uses PNS computations in its chemotactile oral veil (OV) in prey tracking, averaging olfactory stimuli across the OV to target likely source direction, or "stimulus place". This suggests a peripheral subepithelial network (SeN) interconnecting sensory sites to compute the directional average. We pursued anatomy and connectivity of previously described ciliated putative sensory cells on OV papillae. Scanning electron microscopy (SEM) confirmed paddle-shaped cilia in clusters. Anti-tubulin and phalloidin staining showed connections to branching nervelets and muscle fibers for contraction and expansion of papillae. Ciliary cell processes could not be traced into nerves, consistent with sensory transmission to CNS via secondary afferents. Anti-tyrosine hydroxylase-stained ciliated cells in clusters and revealed an at least partially dopaminergic subepithelial network interconnecting clusters near and distant, connections consistent with PNS averaging of multiple stimulated loci. Other, unidentified, SeN neurotransmitters are likely. Confirming chemotactile functions, perfusible suction electrodes recorded ciliary spiking excited by both mechanical and appetitive chemical stimuli. Stimuli induced sensory nerve spiking like that encoding stimulus place. Sensory nerve spikes and cilia cluster spikes were not identifiable as generated by the same neurons. Ciliary clusters likely drive the sensory nerve spikes via SeN, mediating appetitive and stimulus place codes to CNS. These observations may facilitate future analyses of the PNS in odor discrimination and memory, and also suggest such SeNs as potential evolutionary precursors of CNS place-coding circuitry in the segmented, skeletonized protostomes and deuterostomes.
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Affiliation(s)
- Tigran Norekian
- Whitney Laboratory for Marine Biosciences, University of Florida, St. Augustine, Florida, United States of America
- Friday Harbor Laboratories, University of Washington, Friday Harbor, Washington, United States of America
| | - Yichen Liu
- Department of Molecular & Integrative Physiology, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
| | - Ekaterina D. Gribkova
- Coordinated Science Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
- Neuroscience Program, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
| | - Jilai Cui
- Neuroscience Program, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
| | - Rhanor Gillette
- Coordinated Science Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
- Neuroscience Program, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
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3
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Brown JW, Berg OH, Boutko A, Stoerck C, Boersma MA, Frost WN. Neural division of labor: the gastropod Berghia defends against attack using its PNS to retaliate and its CNS to erect a defensive screen. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.29.551068. [PMID: 37577477 PMCID: PMC10418079 DOI: 10.1101/2023.07.29.551068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/15/2023]
Abstract
Relatively little is known about how the peripheral nervous system (PNS) contributes to the patterning of behavior, in which its role transcends the simple execution of central motor commands or mediation of reflexes. We sought to draw inferences to this end in the aeolid nudibranch Berghia stephanieae, which generates a rapid, dramatic defense behavior, "bristling." This behavior involves the coordinated movement of cerata, dozens of venomous appendages emerging from the animal's mantle. Our investigations revealed that bristling constitutes a stereotyped but non-reflexive two-stage behavior: an initial adduction of proximate cerata to sting the offending stimulus (Stage 1), followed by a coordinated radial extension of remaining cerata to create a pincushion-like defensive screen around the animal (Stage 2). In decerebrated specimens, Stage 1 bristling was preserved, while Stage 2 bristling was replaced by slower, uncoordinated, and ultimately maladaptive ceratal movements. We conclude from these observations that 1) the PNS and central nervous system (CNS) mediate Stages 1 and 2 of bristling, respectively; 2) the behavior propagates through the body utilizing both peripheral- and central-origin nerve networks that support different signaling kinetics; and 3) the former network inhibits the latter in the body region being stimulated. These findings extend our understanding of the PNS's computational capacity and provide insight into a neuroethological scheme that may generalize across cephalized animals, in which the CNS and PNS both independently and interactively pattern different aspects of non-reflexive behavior.
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Affiliation(s)
- Jeffrey W. Brown
- Stanson Toshok Center for Brain Function and Repair, Rosalind Franklin University of Medicine and Science, North Chicago, IL 60064
- School of Graduate and Postdoctoral Studies, Rosalind Franklin University of Medicine and Science, North Chicago, IL 60064
| | - Ondine H. Berg
- Neuroscience Program, Lake Forest College, Lake Forest, IL 60045
| | - Anastasiya Boutko
- The Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, IL 60064
| | - Cody Stoerck
- Department of Psychology, California State University at Fullerton, Fullerton, CA 92831
| | | | - William N. Frost
- Stanson Toshok Center for Brain Function and Repair, Rosalind Franklin University of Medicine and Science, North Chicago, IL 60064
- School of Graduate and Postdoctoral Studies, Rosalind Franklin University of Medicine and Science, North Chicago, IL 60064
- The Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, IL 60064
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Alesci A, Pergolizzi S, Mokhtar DM, Fumia A, Aragona M, Lombardo GP, Messina E, D'Angelo R, Lo Cascio P, Sayed RKA, Albano M, Capillo G, Lauriano ER. Morpho-structural adaptations of the integument in different aquatic organisms. Acta Histochem 2023; 125:152031. [PMID: 37075648 DOI: 10.1016/j.acthis.2023.152031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 04/12/2023] [Accepted: 04/13/2023] [Indexed: 04/21/2023]
Abstract
The integument acts as a barrier to protect the body from harmful pathogenic infectious agents, parasites, UV rays, trauma, and germs. The integument of invertebrates and vertebrates are structurally different: while invertebrates usually have a simple monolayer epidermis frequently covered by mucus, cuticles, or mineralized structures, vertebrates possess a multilayered epidermis with several specialized cells. This study aims to describe by morphological, histological, and immunohistochemical analyses, the morpho-structural adaptations throughout evolution of the integument of gastropod Aplysia depilans (Gmelin, 1791), ascidian Styela plicata (Lesuer, 1823), myxine hagfish Eptatretus cirrhatus (Forster, 1801) and teleost Heteropneustes fossilis (Bloch, 1794) for the first time, with special reference to sensory epidermal cells. Different types of cells could be identified that varied according to the species; including mucous cells, serous glandular cells, clavate cells, club cells, thread cells, and support cells. In all integuments of the specimens analyzed, sensory solitary cells were identified in the epidermis, immunoreactive to serotonin and calbindin. Our study provided an essential comparison of integuments, adding new information about sensory epidermal cells phylogenetic conservation and on the structural changes that invertebrates and vertebrates have undergone during evolution.
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Affiliation(s)
- Alessio Alesci
- Department of Chemical, Biological, Pharmaceutical, and Environmental Sciences, University of Messina, 98166 Messina, Italy.
| | - Simona Pergolizzi
- Department of Chemical, Biological, Pharmaceutical, and Environmental Sciences, University of Messina, 98166 Messina, Italy
| | - Doaa M Mokhtar
- Department of Anatomy and Histology, Faculty of Veterinary Medicine, Assiut University, Assiut 71526, Egypt
| | - Angelo Fumia
- Department of Clinical and Experimental Medicine, University of Messina, Padiglione C, A. O. U. Policlinico "G. Martino", 98124 Messina, Italy.
| | - Marialuisa Aragona
- Department of Veterinary Sciences, University of Messina, 98168 Messina, Italy
| | - Giorgia Pia Lombardo
- Department of Chemical, Biological, Pharmaceutical, and Environmental Sciences, University of Messina, 98166 Messina, Italy
| | - Emmanuele Messina
- Department of Chemical, Biological, Pharmaceutical, and Environmental Sciences, University of Messina, 98166 Messina, Italy
| | - Roberta D'Angelo
- Department of Chemical, Biological, Pharmaceutical, and Environmental Sciences, University of Messina, 98166 Messina, Italy
| | - Patrizia Lo Cascio
- Department of Chemical, Biological, Pharmaceutical, and Environmental Sciences, University of Messina, 98166 Messina, Italy
| | - Ramy K A Sayed
- Department of Anatomy and Embryology, Faculty of Veterinary Medicine, Sohag University, Sohag 82524, Egypt
| | - Marco Albano
- Department of Veterinary Sciences, University of Messina, 98168 Messina, Italy
| | - Gioele Capillo
- Department of Veterinary Sciences, University of Messina, 98168 Messina, Italy; Institute for Marine Biological Resources and Biotechnology (IRBIM), National Research Council (CNR), Section of Messina, 98100 Messina, Italy
| | - Eugenia Rita Lauriano
- Department of Chemical, Biological, Pharmaceutical, and Environmental Sciences, University of Messina, 98166 Messina, Italy
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Beach GA, Habib MR, El Hiani Y, Miller MW, Croll RP. Localization of keyhole limpet hemocyanin-like immunoreactivity in the nervous system of Biomphalaria alexandrina. J Neurosci Res 2019; 97:1469-1482. [PMID: 31379045 PMCID: PMC10401489 DOI: 10.1002/jnr.24497] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Revised: 06/14/2019] [Accepted: 07/03/2019] [Indexed: 01/16/2023]
Abstract
Recent years have led to increased effort to describe and understand the peripheral nervous system and its influence on central mechanisms and behavior in gastropod molluscs. This study revealed that an antibody raised against keyhole limpet hemocyanin (KLH) cross-reacts with an antigen(s) found extensively in both the central and the peripheral nervous systems of Biomphalaria alexandrina. The results revealed KLH-like immunoreactive (LIR) neurons in the cerebral, pedal, buccal, left pleural, right parietal, and visceral ganglion within the CNS with fibers projecting throughout all the peripheral nerves. Numerous KLH-LIR peripheral sensory neurons located in the foot, lips, tentacles, mantle, esophagus, and penis exhibited a bipolar morphology with long tortuous dendrites. KLH-LIR cells were also present in the eye and statocyst, thus suggesting the labeling of multiple sensory modalities/cell types. KLH-LIR cells did not co-localize with tyrosine hydroxylase (TH)-LIR cells, which have previously been described in this and other gastropods. The results thus provide descriptions of thousands of peripheral sensory neurons, not previously described in detail. Future research should seek to pair sensory modalities with peripheral cell type and attempt to further elucidate the nature of KLH-like reactivity. These findings also emphasize the need for caution when analyzing results obtained through use of antibodies raised against haptens conjugated to carrier proteins, suggesting the need for stringent controls to help limit potential confounds caused by cross-reactivity. In addition, this study is the first to describe neuronal cross-reactivity with KLH in Biomphalaria, which could provide a substrate for host-parasite interactions with a parasitic trematode, Schistosoma.
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Affiliation(s)
- Griffin A Beach
- Department of Physiology & Biophysics, Dalhousie University, Halifax, NS, Canada
| | - Mohamed R Habib
- Medical Malacology Laboratory, Theodor Bilharz Research Institute, Giza, Egypt
| | - Yassine El Hiani
- Department of Physiology & Biophysics, Dalhousie University, Halifax, NS, Canada
| | - Mark W Miller
- Institute of Neurobiology, University of Puerto Rico Medical Sciences Campus, San Juan, Puerto Rico.,Department of Anatomy & Neurobiology, University of Puerto Rico Medical Sciences Campus, San Juan, Puerto Rico
| | - Roger P Croll
- Department of Physiology & Biophysics, Dalhousie University, Halifax, NS, Canada
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Abstract
Gastropod diversity is substantial in marine and freshwater habitats, and many aquatic slugs and snails use olfactory cues to guide their navigation behaviour. Examples include finding prey or avoiding predators based on kairomones, or finding potential mates using pheromones. Here, I review the diversity of navigational behaviours studied across the major aquatic taxa of gastropods. I then synthesize evidence for the different theoretical navigation strategies the animals may use. It is likely that gastropods regularly use either chemotaxis or odour-gated rheotaxis (or both) during olfactory-based navigation. Finally, I collate the patchwork of research conducted on relevant proximate mechanisms that could produce navigation behaviours. Although the tractability of several gastropod species for neurophysiological experimentation has generated some valuable insight into how turning behaviour is triggered by contact chemoreception, there remain many substantial gaps in our understanding for how navigation relative to more distant odour sources is controlled in gastropods. These gaps include little information on the chemoreceptors and mechanoreceptors (for detecting flow) found in the peripheral nervous system and the central (or peripheral) processing circuits that integrate that sensory input. In contrast, past studies do provide information on motor neurons that control the effectors that produce crawling (both forward locomotion and turning). Thus, there is plenty of scope for further research on olfactory-based navigation, exploiting the tractability of gastropods for neuroethology to better understand how the nervous system processes chemosensory input to generate movement towards or away from distant odour sources.
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Affiliation(s)
- Russell C Wyeth
- Biology Department, St Francis Xavier University, 2321 Notre Dame Avenue, Antigonish, NS, Canada B2G 2W5
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Brown JW, Schaub BM, Klusas BL, Tran AX, Duman AJ, Haney SJ, Boris AC, Flanagan MP, Delgado N, Torres G, Rolón-Martínez S, Vaasjo LO, Miller MW, Gillette R. A role for dopamine in the peripheral sensory processing of a gastropod mollusc. PLoS One 2018; 13:e0208891. [PMID: 30586424 PMCID: PMC6306152 DOI: 10.1371/journal.pone.0208891] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Accepted: 11/27/2018] [Indexed: 11/26/2022] Open
Abstract
Histological evidence points to the presence of dopamine (DA) in the cephalic sensory organs of multiple gastropod molluscs, suggesting a possible sensory role for the neurotransmitter. We investigated the sensory function of DA in the nudipleuran Pleurobranchaea californica, in which the central neural correlates of sensation and foraging behavior have been well characterized. Tyrosine hydroxylase-like immunoreactivity (THli), a signature of the dopamine synthetic pathway, was similar to that found in two other opisthobranchs and two pulmonates previously studied: 1) relatively few (<100) THli neuronal somata were observed in the central ganglia, with those observed found in locations similar to those documented in the other snails but varying in number, and 2) the vast majority of THli somata were located in the peripheral nervous system, were associated with ciliated, putative primary sensory cells, and were highly concentrated in chemotactile sensory organs, giving rise to afferent axons projecting to the central nervous system. We extended these findings by observing that applying a selective D2/D3 receptor antagonist to the chemo- and mechanosensory oral veil-tentacle complex of behaving animals significantly delayed feeding behavior in response to an appetitive stimulus. A D1 blocker had no effect. Recordings of the two major cephalic sensory nerves, the tentacle and large oral veil nerves, in a deganglionated head preparation revealed a decrease of stimulus-evoked activity in the former nerve following application of the same D2/D3 antagonist. Broadly, our results implicate DA in sensation and engender speculation regarding the foraging-based decisions the neurotransmitter may serve in the nervous system of Pleurobranchaea and, by extension, other gastropods.
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Affiliation(s)
- Jeffrey W. Brown
- Program in Biophysics and Computational Biology, University of Illinois, Urbana, Illinois, United States of America
- College of Medicine, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
- * E-mail:
| | - Brittany M. Schaub
- School of Molecular and Cellular Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
| | - Bennett L. Klusas
- School of Molecular and Cellular Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
| | - Andrew X. Tran
- School of Integrative Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
| | - Alexander J. Duman
- School of Integrative Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
| | - Samantha J. Haney
- School of Molecular and Cellular Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
| | - Abigail C. Boris
- School of Molecular and Cellular Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
| | - Megan P. Flanagan
- School of Integrative Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
| | - Nadia Delgado
- Institute of Neurobiology and Department of Anatomy & Neurobiology, University of Puerto Rico, Medical Sciences Campus, San Juan, Puerto Rico, United States of America
| | - Grace Torres
- Institute of Neurobiology and Department of Anatomy & Neurobiology, University of Puerto Rico, Medical Sciences Campus, San Juan, Puerto Rico, United States of America
| | - Solymar Rolón-Martínez
- Institute of Neurobiology and Department of Anatomy & Neurobiology, University of Puerto Rico, Medical Sciences Campus, San Juan, Puerto Rico, United States of America
| | - Lee O. Vaasjo
- Institute of Neurobiology and Department of Anatomy & Neurobiology, University of Puerto Rico, Medical Sciences Campus, San Juan, Puerto Rico, United States of America
| | - Mark W. Miller
- Institute of Neurobiology and Department of Anatomy & Neurobiology, University of Puerto Rico, Medical Sciences Campus, San Juan, Puerto Rico, United States of America
| | - Rhanor Gillette
- Program in Biophysics and Computational Biology, University of Illinois, Urbana, Illinois, United States of America
- School of Molecular and Cellular Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois, United States of America
- Department of Molecular & Integrative Physiology and the Neuroscience Program, University of Illinois, Urbana, Illinois, United States of America
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Webber MP, Thomson JWS, Buckland-Nicks J, Croll RP, Wyeth RC. GABA-, histamine-, and FMRFamide-immunoreactivity in the visual, vestibular and central nervous systems of Hermissenda crassicornis. J Comp Neurol 2017; 525:3514-3528. [PMID: 28726311 DOI: 10.1002/cne.24286] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Revised: 02/23/2017] [Accepted: 02/28/2017] [Indexed: 11/12/2022]
Abstract
Hermissenda crassicornis is a model for studying the molecular and cellular basis for classical conditioning, based on its ability to associate light with vestibular stimulation. We used confocal microscopy to map histamine (HA), FMRF-amide, and γ-aminobutyric acid (GABA) immunoreactivity in the central nervous system (CNS), eyes, optic ganglia and statocysts of the nudibranchs. For HA immunoreactivity, we documented both consistently and variably labeled CNS structures across individuals. We also noted minor differences in GABA immunoreactivity in the CNS compared to previous work on Hermissenda. Contrary to expectations, we found no evidence for GABA inside the visual or vestibular systems. Instead, we found only FMRFamide- and HA immunoreactivity (FMRFamide: 4 optic ganglion cells, 4-5 hair cells; HA: 3 optic ganglion cells, 8 hair cells). Overall, our results can act as basis for comparisons of nervous systems across nudibranchs, and suggest further exploration of intraspecific plasticity versus evolutionary changes in gastropod nervous systems.
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Affiliation(s)
- Marissa P Webber
- Department of Biology, St. Francis Xavier University, Antigonish, Nova Scotia, Canada
| | - James W S Thomson
- Department of Biology, St. Francis Xavier University, Antigonish, Nova Scotia, Canada
| | - Johnny Buckland-Nicks
- Department of Biology, St. Francis Xavier University, Antigonish, Nova Scotia, Canada
| | - Roger P Croll
- Department of Physiology and Biophysics, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Russell C Wyeth
- Department of Biology, St. Francis Xavier University, Antigonish, Nova Scotia, Canada
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