Chelsea M. Haakenson, Jacques Balthazart, Jonathan W. VanRyzin, Ashley E. Marquardt, Sydney E. Ashton, Margaret M. McCarthy, Gregory F. Ball
{"title":"Neurochemical Characterization of Dopaminoceptive Cells in Song Control Nuclei of Canaries and Their Activation During Song Production: A Multiplex Fluorescent In Situ Hybridization Study","authors":"Chelsea M. Haakenson, Jacques Balthazart, Jonathan W. VanRyzin, Ashley E. Marquardt, Sydney E. Ashton, Margaret M. McCarthy, Gregory F. Ball","doi":"10.1002/cne.25675","DOIUrl":"https://doi.org/10.1002/cne.25675","url":null,"abstract":"<p>Highly sensitive in situ hybridization procedures (RNAScope) were used to quantify the expression of three dopamine receptors (Drd1, Drd2, and Drd3) in two song control nuclei (HVC and the Area X of the basal ganglia) that are known to receive dopaminergic inputs and in the periaqueductal gray (PAG) of male and female canaries. Both sexes were treated with testosterone to ensure they would sing actively. We also determined the excitatory versus inhibitory phenotype of the cells expressing these receptors as well as their activation following a period of song production. The three receptor types were identified in each brain area, with the exception of Drd3 in Area X. The density of cells expressing each receptor varied as a function of receptor type and brain area. Surprisingly few sex differences were detected; they do not seem to explain the sex differences in testosterone-induced song. Overall, the density of Drd-positive cells was much lower in PAG than in the two song control nuclei. In HVC, the majority of cells expressing the three receptor subtypes were VGlut2-positive, whereas colocalization with Vglut2 occurred in few cells in Area X and in an intermediate proportion of cells in PAG. The number of inhibitory cells expressing dopamine receptors was limited. Most dopaminoceptive cells in Area X did not express either excitatory or inhibitory markers. Finally, cellular activation during singing behavior, as measured by the expression of Egr1, was observed in cells expressing each of the three dopamine receptor subtypes, except Drd3 in the PAG.</p>","PeriodicalId":15552,"journal":{"name":"Journal of Comparative Neurology","volume":"532 10","pages":""},"PeriodicalIF":2.3,"publicationDate":"2024-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/cne.25675","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142429832","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":"Structural Basis for Histaminergic Regulation of Neural Circuits in the Mouse Olfactory Bulb","authors":"Yukari Minami-Ogawa, Emi Kiyokage, Haruyo Yamanishi, Sawa Horie, Satoshi Ichikawa, Kazunori Toida","doi":"10.1002/cne.25671","DOIUrl":"https://doi.org/10.1002/cne.25671","url":null,"abstract":"<div>\u0000 \u0000 <p>Odor information is modulated by centrifugal inputs from other brain regions to the olfactory bulb (OB). Neurons containing monoamines, such as serotonin, acetylcholine, and noradrenaline, are well known as centrifugal inputs; however, the role of histamine, which is also present in the OB, is not well understood. In this study, we examined the histaminergic neurons projecting from the hypothalamus to the OB. We used an antibody against histidine decarboxylase (HDC), a synthesizing enzyme of histamine, to identify histaminergic neurons and assess their localization within the OB and the ultrastructure of their fibers and synapses using multiple immunostaining laser microscopy, ultra-high voltage electron microscopy (EM), and EM to confirm their relationships with other neurons. To further identify the origin nucleus of the histaminergic neurons projecting to the OB, we injected the retrograde tracer FluoroGold and analyzed the pathway to the OB anterogradely. HDC-immunoreactive (-ir) fibers were abundant in the olfactory nerve (ON) layer compared to other monoamines. HDC-ir neurons received asymmetrical synapses from ONs and formed synapses containing pleomorphic vesicles with variable postsynaptic densities to non-ON elements, thus forming serial synapses. We also confirmed that histaminergic neurons project from the rostral ventral tuberomammillary nucleus to the granule cell layer of the OB and, for the first time, successfully visualized their axons from the hypothalamus to the OB. These findings indicate that histamine may regulate odor discrimination in the OB, suggesting a regulatory relationship between hypothalamic function and olfaction. We thus elucidate morphological mechanisms with tuberomammillary nucleus–derived histaminergic neurons involved in olfactory information.</p>\u0000 </div>","PeriodicalId":15552,"journal":{"name":"Journal of Comparative Neurology","volume":"532 10","pages":""},"PeriodicalIF":2.3,"publicationDate":"2024-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142429833","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":"Fish That Fish for Fish—A Peculiar Location of “Fishing Motoneurons” in the Striated Frogfish Antennarius striatus","authors":"Hanako Hagio, Hirotaka Nishino, Kenta Miyake, Nene Sato, Kei Sawada, Tomoya Nakayama, Naoyuki Yamamoto","doi":"10.1002/cne.25674","DOIUrl":"10.1002/cne.25674","url":null,"abstract":"<p>In lophiform teleosts, the first dorsal fin has evolved as a specialized structure called the “illicium” equipped with the esca, which is a modified skin flap used to attract small fish for predation. The motor control system of the illicium, however, remained unknown. The present study investigated the innervation of muscles for the illicium and morphology of motoneurons innervating them in the striated frogfish <i>Antennarius striatus</i>. We found that the dorsal ramus of occipital nerve innervates the muscles. Motoneurons for the illicium are present in the dorsolateral zone of ventral horn at the medullo-spinal boundary level, forming a cluster somewhat distinct from other motoneurons of the ventral horn. Motoneurons for the second to fourth dorsal fins and pectoral fin were located in the ventrolateral and ventromedial zones of ventral horn, respectively, whereas those of the dorsal trunk muscle in the dorsomedial zone of ventral horn. Motoneurons for the first dorsal spine of white-spotted pygmy filefish were also investigated for species comparison and were found to locate in the ventrolateral zone of ventral horn, similarly to the motoneurons for the second to fourth dorsal fins of the frogfish. These results suggest that motoneurons for the illicium have become segregated from other motoneurons to be situated in an unusual dorsal position for a motoneuron pool of a dorsal fin, in concert with the evolution of specialized “fishing behavior” performed by the illicium.</p>","PeriodicalId":15552,"journal":{"name":"Journal of Comparative Neurology","volume":"532 10","pages":""},"PeriodicalIF":2.3,"publicationDate":"2024-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/cne.25674","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142390943","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}
Omprakash Singh, Sumela Basu, Abhinav Srivastava, Dipti R. Pradhan, Pallabi Dandapat, Chandramohan Bathrachalam, Praful S. Singru
{"title":"Cocaine- and Amphetamine-Regulated Transcript Peptide in the Central Nervous System of the Gecko, Hemidactylus leschenaultii: Molecular Characterization, Neuroanatomical Organization, and Regulation by Neuropeptide Y","authors":"Omprakash Singh, Sumela Basu, Abhinav Srivastava, Dipti R. Pradhan, Pallabi Dandapat, Chandramohan Bathrachalam, Praful S. Singru","doi":"10.1002/cne.25672","DOIUrl":"10.1002/cne.25672","url":null,"abstract":"<p>Neuropeptide cocaine- and amphetamine-regulated transcript (CART) is widely expressed in the brains of teleosts, amphibians, birds, and mammals and has emerged as a conserved regulator of energy balance across these vertebrate phyla. However, as yet, there is no information on CART in the reptilian brain. We characterized the cDNA encoding CART and mapped CART-containing elements in the brain of gecko, <i>Hemidactylus leschenaultii</i> (<i>hl</i>) using a specific anti-CART antiserum. We report a 683-bp <i>hlcart</i> transcript containing a 336-bp open reading frame, which encodes a putative 111-amino acid hl-preproCART. The 89-amino acid hl-proCART generated from hl-preproCART produced two putative bioactive hl-CART-peptides. These bioactive CART-peptides were > 93% similar with those in rats/humans. Although reverse transcription-polymerase chain reaction (RT-PCR) detected <i>hlcart</i>-transcript in the brain, CART-containing neurons/fibers were widely distributed in the telencephalon, diencephalon, mesencephalon, rhombencephalon, spinal cord, and retina. The mitral cells in olfactory bulb, neurons in the paraventricular, periventricular, arcuate (Arc), Edinger–Westphal, and brainstem nuclei were intensely CART-positive. In view of antagonistic roles of neuropeptide Y (NPY) and CART in energy balance in the framework of mammalian hypothalamus, we probed CART–NPY interaction in the hypothalamus of <i>H. leschenaultii</i>. Double immunofluorescence showed a dense NPY-innervation of Arc CART neurons. <i>Ex vivo</i> hypothalamic slices treated with NPY/NPY-Y<sub>1</sub>-receptor agonist significantly reduced <i>hlcart</i>-mRNA levels in the Arc-containing tissues and CART-ir in the dorsal-Arc. However, CART-ir in ventral-Arc was unaffected. NPY via Y<sub>1</sub>-receptors may regulate energy balance by inhibiting dArc CART neurons. This study on CART in a reptilian brain fills the current void in literature and underscores the conserved feature of the neuropeptide across the entire vertebrate phyla.</p>","PeriodicalId":15552,"journal":{"name":"Journal of Comparative Neurology","volume":"532 10","pages":""},"PeriodicalIF":2.3,"publicationDate":"2024-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/cne.25672","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142390942","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}
Aleksandr Veshchitskii, Polina Shkorbatova, Evgeniya Efimova, Natalia Merkulyeva
{"title":"Inter-Strain Differences in the Lumbar Spinal Cord Anatomy and Neuromorphology: Wistar Versus Dark Agouti Rats","authors":"Aleksandr Veshchitskii, Polina Shkorbatova, Evgeniya Efimova, Natalia Merkulyeva","doi":"10.1002/cne.25673","DOIUrl":"10.1002/cne.25673","url":null,"abstract":"<div>\u0000 \u0000 <p>Rat strains differ in physiology, behavior, and recovery after central nervous system injury. To assess these differences, we compared the gross and local anatomy and neuromorphology of the lumbar spinal cord of the Wistar and Dark Agouti (DA) strains. The key findings include (i) distinct spatial relationships between vertebrae and spinal segments in the two strains; (ii) Wistar rats have larger volumes of spinal cord gray and white matter; (iii) DA rats have smaller total neuronal populations, thus indicating an expectation of smaller local neuronal populations; (iv) this expectation was confirmed for interneurons expressing calbindin 28 kDa. But contrary to expectations, (v) DA rats had more numerous populations of the interneurons expressing parvalbumin and a population of α-motoneurons. Consequently, these strains displayed divergent ratios in specific spinal neuronal populations. Researchers should consider these inter-strain differences when comparing data across different strains.</p>\u0000 </div>","PeriodicalId":15552,"journal":{"name":"Journal of Comparative Neurology","volume":"532 10","pages":""},"PeriodicalIF":2.3,"publicationDate":"2024-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142390944","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}
Carol A. Barnes, Michele R. Permenter, Julie A. Vogt, Kewei Chen, Thomas G. Beach
{"title":"Cover Image, Volume 532, Issue 9","authors":"Carol A. Barnes, Michele R. Permenter, Julie A. Vogt, Kewei Chen, Thomas G. Beach","doi":"10.1002/cne.25676","DOIUrl":"https://doi.org/10.1002/cne.25676","url":null,"abstract":"<p>The cover image is based on the Article <i>Human Alzheimer's Disease ATN/ABC Staging Applied to Aging Rhesus Macaque Brains: Association With Cognition and MRI-Based Regional Gray Matter Volume</i> by Carol A. Barnes et al., https://doi.org/10.1002/cne.25670.\u0000 \u0000 <figure>\u0000 <div><picture>\u0000 <source></source></picture><p></p>\u0000 </div>\u0000 </figure></p>","PeriodicalId":15552,"journal":{"name":"Journal of Comparative Neurology","volume":"532 9","pages":""},"PeriodicalIF":2.3,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/cne.25676","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142324566","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}
Carol A. Barnes, Michele R. Permenter, Julie A. Vogt, Kewei Chen, Thomas G. Beach
{"title":"Human Alzheimer's Disease ATN/ABC Staging Applied to Aging Rhesus Macaque Brains: Association With Cognition and MRI-Based Regional Gray Matter Volume","authors":"Carol A. Barnes, Michele R. Permenter, Julie A. Vogt, Kewei Chen, Thomas G. Beach","doi":"10.1002/cne.25670","DOIUrl":"10.1002/cne.25670","url":null,"abstract":"<div>\u0000 \u0000 <p>The brain changes of Alzheimer's disease (AD) include Abeta (Aβ) amyloid plaques (“A”), abnormally phosphorylated tau tangles (“T”), and neurodegeneration (“N”). These have been used to construct in vivo and postmortem diagnostic and staging classifications for evaluating the spectrum of AD in the “ATN” and “ABC” (“B” for Braak tau stage, “C” for Consortium to Establish a Registry for Alzheimer's Disease [CERAD] neuritic plaque density) systems. Another common AD feature involves cerebral amyloid angiopathy (CAA). We report the first experiment to examine relationships among cognition, brain distribution of amyloid plaques, CAA, tau/tangles, and magnetic resonance imaging (MRI)-determined volume changes (as a measure of “N”) in the same group of behaviorally characterized nonhuman primates. Both ATN and ABC systems were applied to a group of 32 rhesus macaques aged between 7 and 33 years. When an immunohistochemical method for “T” and “B” was used, some monkeys were “triple positive” on ATN, with a maximum ABC status of A1B2C3. With silver or thioflavin S methods, however, all monkeys were classified as T-negative and B0, indicating the absence of mature neurofibrillary tangles (NFTs) and hence neuropathologically defined AD. Although monkeys at extremes of the ATN and ABC classifications, or with frequent CAA, had significantly lower scores on some cognitive tests, the lack of fully mature NFTs or dementia-consistent cognitive impairment indicates that fully developed AD may not occur in rhesus macaques. There were sex differences noted in the types of histopathology present, and only CAA was significantly related to gray matter volume.</p>\u0000 </div>","PeriodicalId":15552,"journal":{"name":"Journal of Comparative Neurology","volume":"532 9","pages":""},"PeriodicalIF":2.3,"publicationDate":"2024-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142307860","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}
Molly T. Karl, Young Do Kim, Kavita Rajendran, Paul R. Manger, Chet C. Sherwood
{"title":"Invariance of Mitochondria and Synapses in the Primary Visual Cortex of Mammals Provides Insight Into Energetics and Function","authors":"Molly T. Karl, Young Do Kim, Kavita Rajendran, Paul R. Manger, Chet C. Sherwood","doi":"10.1002/cne.25669","DOIUrl":"https://doi.org/10.1002/cne.25669","url":null,"abstract":"<div>\u0000 \u0000 <p>The cerebral cortex accounts for substantial energy expenditure, primarily driven by the metabolic demands of synaptic signaling. Mitochondria, the organelles responsible for generating cellular energy, play a crucial role in this process. We investigated ultrastructural characteristics of the primary visual cortex in 18 phylogenetically diverse mammals, spanning a broad range of brain sizes from mouse to elephant. Our findings reveal remarkable uniformity in synapse density, postsynaptic density (PSD) length, and mitochondria density, indicating functional and metabolic constraints that maintain these fundamental features. Notably, we observed an average of 1.9 mitochondria per synapse across mammalian species. When considered together with the trend of decreasing neuron density with larger brain size, we find that brain enlargement in mammals is characterized by increasing proportions of synapses and mitochondria per cortical neuron. These results shed light on the adaptive mechanisms and metabolic dynamics that govern cortical ultrastructure across mammals.</p>\u0000 </div>","PeriodicalId":15552,"journal":{"name":"Journal of Comparative Neurology","volume":"532 9","pages":""},"PeriodicalIF":2.3,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142244804","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":"Covariation of Skull and Brain Morphology in Domestic Dogs","authors":"Sophie A. Barton, Marc Kent, Erin E. Hecht","doi":"10.1002/cne.25668","DOIUrl":"https://doi.org/10.1002/cne.25668","url":null,"abstract":"<div>\u0000 \u0000 <p>Despite their distinct embryonic origins, the skull and brain are highly integrated. Understanding the covariation between the skull and brain can shed light on anatomical, cognitive, and behavioral traits in extant and extinct species. Domestic dogs offer a unique opportunity to investigate skull–brain covariation due to their diverse skull morphologies and neural anatomy. To assess this question, we examined <i>T</i>2-weighted MRI studies of 62 dogs from 33 breeds, plus an additional 17 dogs of mixed or unknown breeds. Scans were opportunistically collected from a veterinary teaching hospital of dogs that were referred for neurological examination but did not have grossly observable structural brain abnormalities. As the neurocrania of dogs become broader and shorter, there is a significant decrease in the gray matter volume of the right olfactory bulb, frontal cortex, marginal gyrus, and cerebellum. On the other hand, as the neurocrania of dogs become narrower and longer, there is a significant decrease in the gray matter volume of the olfactory bulb, frontal cortex, temporal cortex, amygdala, hypothalamus, hippocampus, periaqueductal gray, cerebellum, and brainstem. Selective breeding for specific skull shapes may impact canine brain anatomy and function.</p>\u0000 </div>","PeriodicalId":15552,"journal":{"name":"Journal of Comparative Neurology","volume":"532 9","pages":""},"PeriodicalIF":2.3,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142233195","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}
Sammy C. S. Lee, Anlai J. Wei, Paul R. Martin, Ulrike Grünert
{"title":"Thorny and Tufted Retinal Ganglion Cells Express the Transcription Factor Forkhead Proteins Foxp1 and Foxp2 in Marmoset (Callithrix jacchus)","authors":"Sammy C. S. Lee, Anlai J. Wei, Paul R. Martin, Ulrike Grünert","doi":"10.1002/cne.25663","DOIUrl":"10.1002/cne.25663","url":null,"abstract":"<p>The transcription factor forkhead/winged-helix domain proteins Foxp1 and Foxp2 have previously been studied in mouse retina, where they are expressed in retinal ganglion cells named F-mini and F-midi. Here we show that both transcription factors are expressed by small subpopulations (on average less than 10%) of retinal ganglion cells in the retina of the marmoset monkey (<i>Callithrix jacchus</i>). The morphology of Foxp1- and Foxp2-expressing cells was revealed by intracellular DiI injections of immunofluorescent cells. Foxp1- and Foxp2-expressing cells comprised multiple types of wide-field ganglion cells, including broad thorny cells, narrow thorny cells, and tufted cells. The large majority of Foxp2-expressing cells were identified as tufted cells. Tufted cells stratify broadly in the middle of the inner plexiform layer. They resemble broad thorny cells but their proximal dendrites are bare of branches and the distal dendrites branch frequently forming dense dendritic tufts. Double labeling with calretinin, a previously established marker for broad thorny and narrow thorny cells, showed that only a small proportion of ganglion cells co-expressed calretinin and Foxp1 or Foxp2 supporting the idea that the two markers are differentially expressed in retinal ganglion cells of marmoset retina.</p>","PeriodicalId":15552,"journal":{"name":"Journal of Comparative Neurology","volume":"532 8","pages":""},"PeriodicalIF":2.3,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/cne.25663","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142132891","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}