Journal of Comparative Neurology最新文献

{"title":"The Medullary Audio-Vocal Network in the Toad Bombina orientalis.","authors":"Stefan Huggenberger, Wolfgang Walkowiak","doi":"10.1002/cne.70088","DOIUrl":"10.1002/cne.70088","url":null,"abstract":"<p><p>Anurans are an established paradigm to study vocal mechanisms in vertebrates. Regarding the motor patterns, airborne vocalization of most evolutionarily old anurans (Archaeobatrachia) resembles breathing-that is, lung inflation is used to generate sound. Vocal behavior and call timing can be rapidly elicited or modulated by auditory stimulation so that, for example, calls are uttered antiphonally in a chorus to avoid acoustic overlap. Accordingly, in an in vitro preparation of the isolated whole brain of the Chinese fire-bellied toad, Bombina orientalis, motor patterns similar to those of respiration and vocalization can be elicited reliably by stimulation of the posterior (auditory) branchlet of the statoacoustic nerve (N. VIII). Here, we show that audio-vocal integration does not exclusively involve higher brain centers such as mesencephalic torus semicircularis (colliculus inferior) but is in parallel and more rapidly accomplished within the medulla oblongata. We recorded 228 neurons in the areas of motor nuclei of Nn. V, X, and XII. Hypoglossal motor neurons showed fast activation (latency of the first action potential: 9.9 ± 2.3 ms), exceeded by the very fast activation of interneurons within the hypoglossal area (minimum latency of action potential peak 2.9 ms) after N. VIII stimulation. These data support the idea that the area between the roots of the vagal (N. X) and hypoglossal (N. XII) nerves may be a crucial part of the breathing rhythm generator. It suggests that the hypoglossal area plays an important role in controlling the other motor nuclei involved in vocalization. Thus, this post-vagal area may be an important supplementary interface of audio-vocal integration to initiate and coordinate vocal motor patterns and probably inhibit buccal respiration. With this information, a hypothetical motor network of buccal and lung ventilation, as well as vocalization, was constructed.</p>","PeriodicalId":15552,"journal":{"name":"Journal of Comparative Neurology","volume":"533 10","pages":"e70088"},"PeriodicalIF":2.1,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12501926/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145238664","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exceptional Visual-Opsin Coexpression and Phenotypic Diversity in Outer-Retinal Photoreceptors of Caenophidian Snakes.","authors":"Einat Hauzman, Silke Haverkamp, Juliana H Tashiro, Irene L Gügel, Natalia F Torello-Viera, Thaís B Guedes, Pavel Němec, Nicholas R Casewell, Cassandra M Modahl, Maria Ermelinda Oliveira, Ana Lúcia C Prudente, Daniel O Mesquita, Dora Fix Ventura, David J Gower","doi":"10.1002/cne.70092","DOIUrl":"10.1002/cne.70092","url":null,"abstract":"<p><p>Snakes are a valuable yet understudied taxon for investigating evolutionary adaptations in the vertebrate retina. They possess up to three visual pigments: a short-wavelength-sensitive opsin (SWS1), a medium/long-wavelength-sensitive opsin (LWS), and rhodopsin (RH1). Nocturnal snakes have duplex retinas containing both rod and cone photoreceptors, whereas diurnal caenophidian (\"advanced\") snakes exhibit simplex \"all-cone\" retinas, lacking morphologically typical rods. In this study, we analyzed photoreceptor morphology in the retinas of caenophidian snakes using high-resolution scanning electron microscopy (SEM) and examined visual-opsin expression patterns with immunohistochemistry (IHC). Our analyses revealed remarkable interspecific variability in visual-cell morphology. Light microscopy showed that in all sampled diurnal caenophidians, photoreceptors expressing RH1 exhibit a gross cone-like morphology. However, SEM analysis revealed a subset of photoreceptors with distinct features-thinner inner segments and rod-like synaptic terminals-suggesting they are transmuted, cone-like rods. In retinal sections from nocturnal caenophidian snakes, coexpression of the cone opsins SWS1 and LWS in individual cones was observed, whereas rhodopsin expression remained restricted to morphologically typical rods and showed no coexpression. In contrast, diurnal caenophidians commonly coexpress rhodopsin and SWS1 in single cones, with some instances of triple coexpression (SWS1, RH1, and LWS) in single cones. We evaluated the patterns of spatial distribution of RH1- and SWS1-expressing photoreceptors, as well as SWS1 + RH1 multiopsin cones, in wholemounted retinas of ten species. Our findings revealed considerable species-specific variation in photoreceptor density, topography, and opsin coexpression patterns. IHC results suggest that in some species, rhodopsin is not only expressed in transmuted, cone-like rods but may also be co-opted by UV/violet-sensitive (SWS1-expressing) cones. These findings underscore the exceptional diversity and adaptive innovation in snake visual systems. The unique features and striking interspecific differences in their photoreceptors highlight snakes as an outstanding taxon for studying vertebrate visual-system function and evolution.</p>","PeriodicalId":15552,"journal":{"name":"Journal of Comparative Neurology","volume":"533 10","pages":"e70092"},"PeriodicalIF":2.1,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12501914/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145238667","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Glutamatergic and GABAergic Synapses in the Human Spinal Dorsal Horn Revealed With Immunohistochemistry","authors":"Olivia C. Davis,&nbsp;Andrew J. Todd,&nbsp;Theodore J. Price","doi":"10.1002/cne.70091","DOIUrl":"10.1002/cne.70091","url":null,"abstract":"<div>\u0000 \u0000 <p>Primary afferent neurons detect sensory stimuli in the periphery and transmit this information to the dorsal horn of the spinal cord, where it is processed by excitatory and inhibitory controls before being sent to the brain. Our understanding of the synaptic architecture of these spinal circuits in the rodent has been massively advanced using antibodies raised against scaffolding proteins Homer1 and gephyrin, which anchor glutamate and GABA receptors to the membrane, respectively. Few studies have attempted to visualize spinal cord synapses in human tissue, partly due to a lack of high-quality tissue with low postmortem intervals. In this study, we reveal both excitatory and inhibitory synapses at a high resolution in human lumbar spinal cord tissue using Homer1 and gephyrin immunolabeling and show that the basic organization of these proteins within the dorsal horn is similar to that in the rodent. Homer1+ puncta are highly colocalized with ionotropic glutamate receptors, and over 75% are in contact with a presynaptic axon terminal containing the vesicular glutamate transporter 2 (VGluT2). Similarly, most gephyrin+ profiles are coextensive with the GABA_A-α₂ subunit but fewer than 10% colocalize with Homer1+ puncta, confirming the specificity of these markers. Finally, we use Homer1 immunolabeling to demonstrate that primary afferents can form complex synaptic arrangements in human spinal cord. We conclude that these antibodies can be used as reliable tools for the study of human synaptic circuitry, and we have used them to reveal insight into the spinal connections underlying somatosensation that can be expanded upon in future studies.</p>\u0000 </div>","PeriodicalId":15552,"journal":{"name":"Journal of Comparative Neurology","volume":"533 10","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145191818","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Larger Fish Have Larger Brains With More Neurons Across but Not Within Cohorts Raised in Different Growth Conditions","authors":"Magda C. Teles,&nbsp;Gonçalo M. Melo,&nbsp;Suzana Herculano-Houzel,&nbsp;Rui F. Oliveira","doi":"10.1002/cne.70090","DOIUrl":"https://doi.org/10.1002/cne.70090","url":null,"abstract":"<p>Comparative work on brain size variation across vertebrates has shown that larger species have larger brains and that larger brains have more neurons across species in each clade. This trend supports the expectation that larger bodies require larger brains with more neurons but is at odds with the finding that within a species, larger animals do not necessarily have larger brains, and larger brains do not have more neurons. While the latter finding is inconsistent with the expectation that larger brained species evolve through selection of larger brained individuals, the lack of correlation between brain size and numbers of neurons across individuals of a same species might be due to the small range of variation that is typically found within a species. Here, we take advantage of ecologically regulated indeterminate growth exhibited by the cichlid fish tilapia (<i>Oreochromis mossambicus</i>) raised under different population densities to generate an over 30-fold variation in body mass across adult individuals of the same age. We find that across the cohorts of individuals raised with different growth opportunities provided by different population densities, larger animals have larger brains with more neurons that occur at similar neuronal densities, as applies to interspecific scaling in several vertebrate clades. Within each cohort raised at a given population density, however, those animals with more neurons have higher neuronal densities, but not larger brains or bodies, though the latter scale together—as applies to intraspecific scaling in mice and chickens. We conclude that brain size and number of neurons are determined independently across individuals in a population but scale together across cohorts, in step changes that accompany varying opportunities for growth, in the absence of any selection pressure. Based on these results, we propose a model of brain evolution through plastic changes in response to changing environmental opportunities that accounts for intra-, inter-, and clade-specific patterns of brain scaling and diversity.</p>","PeriodicalId":15552,"journal":{"name":"Journal of Comparative Neurology","volume":"533 9","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/cne.70090","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145146482","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cellular Composition of the Brain of a Northern Minke Whale","authors":"Kamilla Avelino-de-Souza,&nbsp;Nina Patzke,&nbsp;Karl Æ. Karlsson,&nbsp;Paul R. Manger,&nbsp;Suzana Herculano-Houzel","doi":"10.1002/cne.70089","DOIUrl":"10.1002/cne.70089","url":null,"abstract":"<p>The largest mammalian brains belong to cetacean species among the cetartiodactyls. Stereological analyses have estimated cetacean numbers of cerebral cortical neurons to be more than the average 16 billion of humans, yet isotropic fractionator estimates in artiodactyls predict that even the largest cetacean brains should have no more than a few billion cortical neurons. Here, we used the isotropic fractionator to investigate these contrasting estimates of neuronal numbers by determining the numbers of neurons and non-neuronal cells forming the brain of a northern minke whale, previously estimated using stereology as containing 12.8 billion cortical neurons (Eriksen and Pakkenberg 2007), and comparing it to our dataset of several dozen mammalian species analyzed with the same method. We report that, with 3.2 billion neurons, the minke whale cerebral cortex conforms to the quantitative scaling rules that apply to other mammals, especially the closely related artiodactyls. The same brain contained a total of 57.4 billion neurons, of which 54.2 billion were cerebellar neurons, matching the expected numbers of a hypothetical artiodactyl brain of similar cerebellar mass. In addition, we found that the northern minke whale brain, with a mass of 2683.9 g, contained 173.4 billion non-neuronal cells, following the universal scaling rules that apply to the brain in all therian mammals examined to date. Thus, how non-neuronal cells are added to the mammalian brain is conserved across therian mammals and is not affected by the transition to an obligatory aquatic life history. Strikingly, we find that the minke whale is an outlier amongst mammals in having almost 18 cerebellar neurons for every neuron in the cerebral cortex, compared to the average ratio of 4, which might be related to infrasonic communication. In addition, with only approximately 88 million neurons, the remainder of the brain (brainstem/diencephalon/subcortical telencephalon) of the northern minke whale exhibited the lowest relative neuronal density of these regions reported in mammalian brains, which might be related to the absence of limbs compared to all other mammalian species. Our results indicate that the number of neurons in cetacean brains has been grossly overestimated by stereological accounts, and place whale brains on par with highly cognitively capable macaws, macaques, baboons, and elephants, but below great apes and humans, in terms of numbers of cortical neurons.</p>","PeriodicalId":15552,"journal":{"name":"Journal of Comparative Neurology","volume":"533 9","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12445405/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145086315","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Organization of Central Retinal Projections in Anna's Hummingbirds (Calypte anna) and Zebra Finches (Taeniopygia castanotis)","authors":"Cristián Gutiérrez-Ibáñez,&nbsp;Julia A. Bowen,&nbsp;Andrea H. Gaede,&nbsp;Douglas L. Altshuler,&nbsp;Douglas R. Wylie","doi":"10.1002/cne.70087","DOIUrl":"https://doi.org/10.1002/cne.70087","url":null,"abstract":"<p>Hummingbirds (family <i>Trochilidae</i>) are easily recognized due to their unique ability to hover. Critical to hovering flight is head and body stabilization. In birds, stabilization during flight is mediated, among other things, by the detection of optic flow, the motion that occurs across the entire retina during self-motion. Given this increased requirement for stabilization, it is not surprising that previous studies have shown that hummingbirds have neural specializations in the visual pathways involved in the detection of optic flow. Particularly, previous studies have found some structural and functional differences in the hummingbird brain, in the pretectal nucleus lentiformis mesencephali (LM): compared to other avian species, LM shows a massive hypertrophy, and LM neurons have unique response properties to optic flow stimuli. Here, we used intraocular injections of a neural tracer, cholera toxin subunit B (CTB) conjugated with a fluorescent molecule, to study the retinal projections in Anna's hummingbirds (<i>Calypte anna</i>) and compare them to those of a similarly sized non-hovering species, the zebra finch (<i>Taeniopygia castanotis</i>). Retinal targets in both birds were similar and correspond closely to those reported in other birds from a variety of avian clades. Importantly, we found differences in the projections to LM between hummingbirds and zebra finches. Consistent with previous reports of specialization of LM, it was more intensely labelled compared to other retinal-recipient nuclei in hummingbirds. Moreover, this increase in intensity was most apparent in the lateral subnucleus. This study reinforces previous evidence that the LM of hummingbirds is adapted to sustain the unique flight abilities of this clade.</p>","PeriodicalId":15552,"journal":{"name":"Journal of Comparative Neurology","volume":"533 9","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/cne.70087","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144998717","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Embryonic Development of Caenorhabditis elegans Sense Organs","authors":"Leland R. Wexler,&nbsp;Irina Kolotuev,&nbsp;Maxwell G. Heiman","doi":"10.1002/cne.70084","DOIUrl":"https://doi.org/10.1002/cne.70084","url":null,"abstract":"<p><i>Caenorhabditis elegans</i> sense organs provide a powerful model for understanding how different cell types interact to assemble a functional organ. Each sense organ is composed of two glial cells, called the sheath and socket, and one or more neurons. A major challenge in studying their development has been the lack of methods to directly observe these structures in the embryo. Here, we mine a recently published high-resolution ultrastructural dataset of a comma-stage embryo that provides an untapped resource for visualizing early developmental events. From this dataset, we reconstructed all head sense organs (two amphid [AM], four cephalic [CEP], six inner labial [IL], four outer labial quadrant [OLQ], and two outer labial lateral [OLL]). Symmetric sense organs were at different stages of morphogenesis, allowing us to infer developmental steps by which they form. First, we found that the sheath glial cell begins wrapping its partner neurons at the distal tip of the dendrites where it self-fuses into a seamless tube and then “zippers” down the dendrite. In many cases, sheath glia wrap the progenitors of partner neurons prior to their terminal division. After sheath wrapping has begun, the socket glia wraps the sheath glia circumferentially before presumably elongating to form the mature sheath–socket channel. We also observed transient interactions not found in the mature animal, such as amphid sheath glia wrapping the AUA neuron, that may reflect ancestral relationships. This study demonstrates the value of large public EM datasets that can be mined for new insights and sheds light on how neurons and glia undergo coordinated morphogenesis.</p>","PeriodicalId":15552,"journal":{"name":"Journal of Comparative Neurology","volume":"533 9","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/cne.70084","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144923386","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Macro- and Microanatomy of the Sympathetic Innervation of the Spleen in Rodents","authors":"Maria Moura,&nbsp;Alice Miranda,&nbsp;Jonas Campos,&nbsp;Andreia G. Pinho,&nbsp;Sara Rito-Fernandes,&nbsp;Carina Soares-Cunha,&nbsp;António J. Salgado,&nbsp;Nuno A. Silva,&nbsp;Susana Monteiro","doi":"10.1002/cne.70086","DOIUrl":"https://doi.org/10.1002/cne.70086","url":null,"abstract":"<p>In recent years, several studies have demonstrated the crucial role played by the sympathetic spleen innervation in regulating immune cell function involving fighting pathogens or tissue injury. These findings have sparked interest across different research fields with a common goal of understanding and manipulating splenic sympathetic activity to modulate immune function and inflammation. However, the anatomical identification of spleen-projecting neurons in rodents presents a considerable challenge, given the multi-compartmentalized location of their cellular components.</p><p>This article addresses this challenge by providing a detailed anatomical dissection guide of the mouse celiac ganglion and splenic nerve, harboring the cell body and projecting axons, respectively. By combining antero- and retrograde neuronal tracing, immunofluorescence, 3D reconstruction, and viral tracing techniques, we validate the connectivity between the celiac ganglion and the spleen and provide insights into their microanatomy. Importantly, we demonstrate the feasibility of viral transduction in these neurons. Additionally, we identified nerve-associated macrophages (NAMs) within the splenic nerve and demonstrated their responsiveness to inflammatory stimuli. Our findings offer a comprehensive anatomical framework for studying spleen-projecting neurons, paving the way for future investigations into their role in immune regulation and inflammation, as well as their manipulation using advanced neurobiological tools.</p>","PeriodicalId":15552,"journal":{"name":"Journal of Comparative Neurology","volume":"533 9","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/cne.70086","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144915080","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Afferent Projections to the Paratenial Nucleus of the Dorsal Midline Thalamus","authors":"Stephanie B. Linley,&nbsp;Amanda K. P. Rojas,&nbsp;Robert P. Vertes","doi":"10.1002/cne.70082","DOIUrl":"https://doi.org/10.1002/cne.70082","url":null,"abstract":"<div>\u0000 \u0000 <p>The dorsal midline thalamus (DMT) is composed of the paraventricular (PV) and paratenial (PT) nuclei. While the anatomical and functional properties of PV are well-established, PT has remarkably received very little attention—even though the efferent projections of PV and PT are very similar. Using a combination of retrograde tracing and immunohistochemistry, we examined the anatomical inputs to PT and compared them with those to the anterior and posterior PV and to the anterodorsal nucleus of the thalamus. In addition, we examined orexinergic and serotonergic afferents to the PT, comparing them with those to other thalamic nuclei. We found that PT and PV receive input from a common set of structures, including the orbitomedial prefrontal cortex, nuclei of the diagonal band, septum, subiculum of the hippocampus, bed nucleus of the stria terminalis, hypothalamus, reticular nucleus of the thalamus, dorsal raphe nucleus, and periaqueductal gray. However, the pattern and density of these various afferents to PT and PV significantly differed. For instance, PT received much stronger inputs from the orbitofrontal cortex, while PV received stronger projections from the subiculum of the hippocampus and more widespread input from the hypothalamus and the brainstem. By comparison, afferents to AD differed from PT (and PV), as AD received substantial input from the retrosplenial and anterior cingulate cortices, and uniquely from the lateral mammillary nucleus. Further, orexinergic (ORX) and serotonergic (5-HT) fibers distributed at best modestly to PT, which contrasted with quite dense ORX and 5-HT innervation of PV. The present findings, essentially representing the first comprehensive examination of afferent projections to PT, show that the inputs to PT mainly arise from limbic forebrain structures—with pronounced projections from the orbitofrontal cortex, nuclei of the diagonal band, and the reticular nucleus of the thalamus. The functional properties of PT partially overlap with those of PV, but as described herein PT also participates in unique affective, cognitive, and motivational behaviors.</p>\u0000 </div>","PeriodicalId":15552,"journal":{"name":"Journal of Comparative Neurology","volume":"533 9","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144915081","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Interrelationship Between Intraepithelial Nerve Endings and Epithelial Cells in the Rat Epiglottis Revealed by Array Tomography With Scanning Electron Microscopy","authors":"Yoshio Yamamoto,&nbsp;Kuniaki Sasaki,&nbsp;Misaki Komuro,&nbsp;Takuya Yokoyama,&nbsp;Nobuaki Nakamuta","doi":"10.1002/cne.70085","DOIUrl":"https://doi.org/10.1002/cne.70085","url":null,"abstract":"<p>Nerve endings in the laryngeal mucosa interact with epithelial cells to generate sensory discharges against various external stimuli. In the present study, we performed array tomography with scanning electron microscopy to examine the morphological interrelationship between intraepithelial nerve endings and epithelial cells in the rat epiglottis. In the epiglottic mucosa, thin nerve fibers/endings and ramified nerve endings were observed in the epithelial layer. Thin nerve fibers/endings had varicosities and terminal swellings, and ran in the shallow grooves of epithelial cells. The varicosities and terminal regions of the nerve fibers/endings were partially associated with epithelial cells, without any identifiable cell junctions or synaptic specializations. On the other hand, intraepithelial ramified nerve endings were detected in the stratified cuboidal epithelium at the base of the epiglottis. The ramified nerve ending consisted of a branched parent axon and large terminal parts that were approximately 3–6 µm in major axis length with irregular contours. The terminal parts of the ramified endings containing numerous mitochondria were closely attached to epithelial cells, as observed in the thin nerve fibers/endings. In conclusion, intraepithelial nerve endings in the epiglottis were in close contact with laryngeal epithelial cells and may be excited by mediators released from epithelial cells in response to various stimuli from the laryngeal lumen.</p>","PeriodicalId":15552,"journal":{"name":"Journal of Comparative Neurology","volume":"533 8","pages":""},"PeriodicalIF":2.1,"publicationDate":"2025-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/cne.70085","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144894209","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}