bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dopamine‐like immunoreactivity in the brain and suboesophageal ganglion of the honeybee
Authors: Schäfer Sabine , Rehder Vincent 
Published: January 2005

AbstractThe distribution of dopamine in the brain and suboesophageal ganglion of the honeybee Apis mellifera was investigated by means of immunocytochemistry with a well‐characterized antiserum against dopamine. The binding of the antiserum in paraffin serial sections was studied with the peroxidase‐antiperoxidase method. Dopamine‐like immunoreactive neurons are present in most parts of the brain and in the suboesophageal ganglion. Only the optic lobes are devoid of label. There are ca. 330 dopamine immunoreactive somata in each brain hemisphere plus respective suboesophageal hemiganglion, which is less than 0.1% of the entire neuronal population. Most of the labelled somata are situated within three clusters: one below the lateral calyx and two in the anterior‐ventral protocerebrum. Other labelled somata lie dispersed or in small groups around the protocerebral bridge, below the optic tubercles, proximal to the ventral rim of the lobula, and in the lateral and ventral somatal rind of the suboesophageal ganglion. Similar to neurons that react with an antiserum against serotonin, the fine processes of dopamine immunoreactive fibers have a varicose appearance which is typical for aminergic neurons. In addition to the neuronal staining, dopamine‐like immunoreactivity is also present in the sheath surrounding the brain and in the retina, where it is not restricted to any particular cell type.A detailed account is given for those neurons and groups of neurons that could be traced and reconstructed in some detail. A common feature of all dopamine immunoreactive fibers is that each fiber invades large volumes of neuropil, suggesting that dopamine is more important in mediating distant rather than local neural interactions.
Morphologies of rabbit retinal ganglion cells with concentric receptive fields
Authors: Amthor Franklin R. , Takahashi Ellen S. , Oyster Clyde W. 
Published: January 2005

AbstractRabbit retinal ganglion cells with concentric receptive fields were intracellularly recorded and stained in the isolated superfused eyecup preparation to relate specific physiological response properties to dendritic morphology. Concentric ganglion cells, as traditionally defined, were those that had On or Off centers with antagonistic surrounds but lacked complex response properties such as direction or orientation selectivity. Concentric cells were classified into different groups by extracellular recordings of their On‐ or Off‐center response sign, excitatory receptive field center size, linearity of spatial summation, and brisk vs. sluggish and transient vs. sustained responses to step changes in light intensity. The cells were then impaled, confirmed in identity during intracellular recording, and iontophoretically injected with horseradish peroxidase for histological analysis. Twenty‐three concentric ganglion cells were recovered and morphometrically analyzed. Their physiological response properties were found to be related to a number of underlying two‐ and three‐dimensional attributes of the cell's dendritic branching patterns. The dendrites of all 20 brisk concentric cells and two of the three sluggish cells were found to ramify narrowly in either the proximal or distal half of the inner plexiform layer, corresponding to whether they are On center or Off center, respectively. One of the sluggish concentric cells was found to have a more complex, partially bistratified ramification. Physiologically identified brisk‐sustained‐linear, brisk‐transient‐nonlinear, brisk‐transient‐linear, and at least two classes of sluggish concentric ganglion cells were stained. Each of these physiological classes appears to exhibit a distinct and identifiable dendritic branching pattern.
Morphologies of rabbit retinal ganglion cells with complex receptive fields
Authors: Amthor Franklin R. , Takahashi Ellen S. , Oyster Clyde W. 
Published: January 2005

AbstractGanglion cells that had complex receptive field properties, namely, On‐Off and On direction‐selective cells, orientation‐selective cells, local edge detectors, and uniformity detectors (suppressed by contrast cells) were recorded in an isolated superfused rabbit eyecup preparation. Cells were first classified by their characteristic extracellular responses to manually controlled stimuli similar to those which have been used in previous in vivo studies. Ganglion cells were then impaled, confirmed in identity by intracellular recording, and iontophoretically injected with horseradish peroxidase for staining. Twenty‐two ganglion cells, which included members of all the major classes mentioned above, were recovered from the visual streak or near periphery. All recovered cells were drawn in camera lucida from flatmounted retinas and entered into a computer as two‐dimensional stick figures; nearly all were three‐dimensionally reconstructed to determine the level and manner of dendritic ramification in the inner plexiform layer (IPL). The location of ganglion cell dendrites in sublaminar regions of the IPL was found to be consistent with the hypothesis of a division of the IPL into excitatory On (promixal) and Off (distal) sublaminae, with some qualifications for particular classes. Each of the complex receptive field ganglion cell classes exhibited a distinctive three‐dimensional dendritic arborization pattern uniquely associated with that physiological class.
Peptidergic neurons in the basal forebrain magnocellular complex of the rhesus monkey
Authors: Walker Lary C. , Koliatsos Vassilis E. , Kitt Cheryl A. , Richardson Russell T. , Rökaeus Åke , Price Donald L. 
Published: January 2005

AbstractThe basal forebrain magnocellular complex of primates is defined by the presence of large, hyperchromic, usually cholinergic neurons in the nucleus basalis of Meynert and nucleus of the diagonal band of Broca. Because there is growing evidence for noncholinergic neuronal elements in the basal forebrain complex, five neuropeptides and the enzyme choline acetyltransferase were studied immunocytochemically in this region of rhesus monkeys. Galaninlike immunoreactivity coexists with choline‐acetyl‐transferase‐like immunoreactivity in most large neurons and in some smaller neurons of the primate nucleus basalis and nucleus of the diagnonal band. Four other peptides show immunoreactivity in more limited regions of the basal forebrain complex, usually in separate smaller, noncholinergic neurons. Numerous small, somatostatinlike‐immunoreactive neurons occupy primarily anterior and intermediate segments of the nucleus basalis, especially laterally and ventrally. Somewhat fewer, small neuropeptide Y‐like‐immunoreactive somata are found in the same regions. Neurons that show neurotensinlike immunoreactivity are slightly larger than cells that contain immunoreactivity for somatostatin or neuropeptide Y, but these neurons also occur mainly in anterior and intermediate parts of the nucleus basalis. Overall, the usually small, leucine‐enkephalin‐like‐immunoreactive neurons are infrequent in the basal forebrain complex and are most abundant in the rostral intermediate nucleus basalis. Thus, neurons that appear to contain somatostatin, neuropeptide Y, neurotensin, or enkephalin mingle with cholinergic/galaninergic neurons only in some subdivisions of the nucleus basalis/nucleus of the diagonal band, and their distributions suggest that some of these small neurons could be associated with structures that overlap with cholinergic neurons of the labyrinthine basal forebrain magnocellular complex. We also have found light microscopic evidence for innervation of basal forebrain cholinergic neurons by boutons that contain galanin‐, somatostatin‐, neuropeptide Y‐, neurotensin‐, or enkephalinlike immunoreactivity. The origins and functions of these putative synapses remain to be determined.
Studies on the cellular architecture of the bed nuclei of the stria terminalis in the rat: II. chemoarchitecture
Authors: Ju G. , Swanson L. W. , Simerly R. B. 
Published: January 2005

AbstractIn a companion paper (Ju and Swanson; J. Comp. Neurol. 280:587–602, '89) we described a parcellation scheme for the bed nuclei of the stria terminalis (BST) that was based on cytoarchitectonic criteria. In the work reported here, antisera to the neuropeptides corticotropin‐releasing hormone, neurotensin, galanin, substance P, and cholecystokinin were used to determine the extent to which immunostained neuronal cell bodies and presumed terminal fields are correlated with this cytoarchitectonic scheme in the adult male rat. The results confirm the validity of the cytoarchitectonic parcellation and provide additional chemoarchitectonic criteria for determining the (as yet still somewhat arbitrarily defined) border between the BST and the ventrally adjacent preoptic region, for distinguishing between the anterior and posterior divisions of the BST, and for identifying and distinguishing between the particular cell groups or nuclei within each division. The projections of each neuropeptide‐containing cell group in various parts of the BST remain to be determined, as do the precise origins of the localized immunoreactive terminal fields identified here.
Afferent and efferent projections of the VIIIth cranial nerve in the lamprey Lampetra japonica
Authors: Koyama Hiromichi , Kishida Reiji , Goris Richard C. , Kusunoki Toyokazu 
Published: January 2005

AbstractAnterograde and retrograde transport of horseradish peroxidase was used to examine the afferent and efferent projections of the VIIIth cranial nerve in the lamprey Lampetra japonica. Ganglion cells of the VIIIth nerve are classified into three types on the basis of their morphology. The central processes of these ganglion cells enter the medulla in two groups: the anterior group (mostly thick fibers) and the posterior group (mostly thin fibers). Afferent fibers mainly terminate within the ipsilateral ventral and octavomotor nuclei of the octavolateralis area and within the granular and molecular layer of the cerebellum. Some fibers terminate in the contralateral cerebellum, the medial and dorsal nuclei of the octavolateralis area, the descending nucleus of the trigeminal nerve, some cranial motor nuclei, and the lateral octavus nucleus, which has not been described previously. This small nucleus is located beneath the descending nucleus of the trigeminal nerve near the obex. Within the ventral nucleus, thin fibers occupy the dorsal part and thick fibers occupy the ventral part. The basic projection pattern of the primary afferents of the VIIIth nerve in the lampreys was similar to that of gnathostome fishes that have been studied to date. Cell bodies of the efferent vestibular neurons are located between the ipsilateral trigeminal motor nucleus and the facial motor nucleus. The lateral location of these cell bodies differs from that of all other fish species that have been studied.
Development of the thalamocortical system: Transient‐crossed projections to the frontal cortex in neonatal rats
Authors: Minciacchi Diego , Granato Alberto 
Published: January 2005

AbstractThe developmental remodeling of thalamic projections to frontal and prefrontal cortical fields was investigated in the rat by using a double retrograde tracing technique. Bilateral cortical injections of fluorescent tracers were made either in neonatal (first or second postnatal day) or in adult animals. In neonates, the cell populations retrogradely labeled from each cortical injection overlapped in a medial thalamic region that included the midline nuclei and the medial part of the mediodorsal nucleus, ventral medial nucleus, and nucleus gelatinosus. In adults, the overlap region was confined within the boundaries of the midline nuclei. Quantitative analysis showed that this overlap area was three times as wide in neonates as in adults. The neurons located in this region projected unilaterally both in neonatal and adult animals; bilaterally projecting cells were virtually absent.In neonates, a second set of contralaterally projecting neurons was found in more lateral thalamic regions. This population consisted of cell clusters in the dorsal part of the central lateral nucleus and in the lateral part of the ventral medial nucleus; scattered cells were also observed throughout other nuclei. This second cell population was represented in part by neurons bifurcating bilaterally. In adult animals, neurons projecting contralaterally were observed only occasionally in the lateral thalamus.The present results demonstrate that the bilaterality of thalamocortical projections undergoes a reduction during postnatal development. The mechanisms underlying this remodeling and the possible functional role of the transient‐crossed thalamocortical system are discussed.
Endogenous opioid systems and the regulation of dendritic growth and spine formation
Authors: Hauser Kurt F. , McLaughlin Patricia J. , Zagon Ian S. 
Published: January 2005

AbstractThe role of endogenous opioid systems (endogenous opioids and opioid receptors) in neuronal development was examined in 10‐ and 21‐day‐old rats by utilizing an opioid antagonist (naltrexone) paradigm. Throughout the first 3 weeks of life, Sprague‐Dawley rats were given daily subcutaneous injections of either 50 mg/kg naltrexone, a dosage that invoked a complete (24 hours/day) receptor blockade, or 1 mg/kg naltrexone, a dosage which intermittently blocked (4–6 hours/day) opioid receptors and exacerbated opioid action; animals injected with sterile water served as controls. Pyramidal cells from the frontoparietal cortex (layer III) and hippocampal field CA1, and cerebellar Purkinje cells, were impregnated by using the Golgi‐Kopsch method; total and mean dendrite segment length, branch frequency, and spine concentration were analyzed morphometrically. Perturbations of endogenous opioid systems caused region‐dependent alterations in dendrite complexity and/or spine concentration in all brain areas. Continuous opioid receptor blockade resulted in dramatic increases in dendrite and/or spine elaboration compared to controls at 10 days in all brain regions; however, these increases were only evident in the hippocampus at 21 days. With intermittent blockade, dendrite and/or spine growth were often subnormal, being predominant at day 21. Our results indicate that endogenous opioid systems are critical regulators of neuronal differentiation, and they control growth through an inhibitory mechanism. Considering previous findings demonstrating that neurobehavioral ontogeny is dependent on endogenous opioid‐opioid receptor interactions, the present results suggest an opioid‐dependent, structure‐function relationship between neuronal and behavioral maturation.
Distribution of proenkephalin‐derived peptides in the brain of Rana esculenta
Authors: Merchenthaler István , Lázár Gyula , Maderdrut Jerome L. 
Published: January 2005

AbstractThe immunocytochemical distribution of authentic proenkephalin‐containing perikarya and nerve fibers in the brain of Rana esculenta was determined with antisera directed toward different epitopes of preproenkephalin. The pattern of proenkephalinlike immunoreactivity was similar with antisera directed toward [Met5]‐enkephalin, [Met5]‐enkephalin‐Arg6, [Met5]‐enkephalin‐Arg6‐Phe7, [Leu5]‐enkephalin, and metorphamide; however, the intensity of the labelling varied depending on the target antigen.Proenkephalin‐containing perikarya were located in all major subdivisions of the brain except the metencephalon. In the telencephalon, immunoreactive perikarya were detected in the dorsal, medial, and lateral pallium; the medial septal nucleus; the dorsal and ventral striatum; and the amygdala. In the diencephalon, immunoreactive perikarya were detected in the preoptic nucleus, in the dorsal and ventral caudal hypothalamus, and in an area that appeared to be homologous to the paraventricular nucleus. In the mesencephalon, numerous immunoreactive perikarya were detected in layer 6 of the optic tectum and a few scattered perikarya were detected in layer 4 of the optic tectum. Immunoreactive perikarya also occurred in the laminar nucleus of the torus semicircularis. In the rhombencephalon, immunoreactive perikarya were detected in the obex region and the nucleus of the solitary tract. Immunoreactive fibers of varying density were observed in all major subdivisions of the brain with the densest accumulations of fibers occurring in the dorsal pallium, the lateral and medial forebrain bundles, the amygdala, the periventricular hypothalamus, the superficial region of the caudolateral brainstem, and in a tract that appeared to be homologous to the tractus solitarius.The extensive system of proenkephalin‐containing perikarya and nerve fibers in the brain of an amphibian showed many similarities to the distribution of proenkephalin‐containing perikarya and nerve fibers previously described for the amniote brain.
Cell production in the chicken cochlea
Authors: Katayama Akiko , Corwin Jeffrey T. 
Published: January 2005

AbstractIn the chicken cochlea, the structural features of the cilia bundles of individual hair cells vary systematically along the length of the sensory epithelium. As a first approach to understanding the developmental mechanisms that underlie this precise arrangement of structurally distinct hair cells, the spatiotemporal pattern of the terminal mitoses of their precursor cells was investigated by administering 3H‐thymidine, a radioactive precursor to DNA. This demonstrated that the first hair cells were produced during the sixth day of incubation and formed a longitudinal band that extended along most of the length of the sensory epithelium. The epithelium grew further through appositional addition of hair cells at the edges of this first band of cells, and the hair cell addition process expanded into the surrounding areas during the next 3 days. By the ninth day of incubation all the hair cells in the sensory epithelium except for those at the peripheral edges in the distal (apex) portion had been produced through terminal mitoses. Our results have demonstrated that hair cells that have similar stereocilia phenotypes do not all leave the mitotic cycle at the same time.
Changes in neuronal cell bodies in N. laminaris during deafferentation‐induced dendritic atrophy
Authors: Deitch Jeffrey S. , Rubel Edwin W. 
Published: January 2005

AbstractN. laminaris dendrites begin to atrophy almost immediately after they are deafferented. Accompanying this rapid change in shape is a loss of microtubules and neurofilaments at the base of the dendrite, and a decrease in the density of the dendritic cytoplasm. However, degenerative changes in the dendritic plasma membrane were not evident until 2 days after deafferentation. Thus it was unknown what happened to the volume and membrane lost from the atrophying dendrites before this time. The soma was investigated in this study as a possible recipient of the volume of the atrophying dendrite. Soma size increased significantly by 2 hours after deafferentation and continued to increase for 1–8 days after deafferentation. The nucleus, which is normally concentric with the soma, moved continuously to the dorsal pole of the soma, toward the innervated side of the cell. The cytoplasm on the ventral side of the soma showed a decrease in density and loss of cytoskeleton similar to what was found in the initial portion of the ventral primary dendrites in the accompanying paper.These changes are interpreted as indicative of a rapid resorption of the ventral dendrite back into the soma following deafferentation.
Gap junction protein in rat hippocampus: Correlative light and electron microscope immunohistochemical localization
Authors: Shiosaka S. , Yamamoto T. , Hertzberg E. L. , Nagy J. I. 
Published: January 2005

AbstractImmunohistochemical techniques and an affinity‐purified antibody directed against the 27‐kD gap‐junctional protein (GJP) from rat liver were used to determine the ultrastructural localization of GJP in the rat hippocampus. At the light microscope level, dense GJP immunoreactivity having a stringlike appearance was seen in a very small percentage of medium‐sized neuronal somata located in the stratum pyramidale, and diffuse immunostaining was seen in many small cell bodies in the stratum pyramidale, stratum oriens, and the alveus. Abundant GJP‐immunoreactive (GJP‐IR) varicose fibers were observed in the strata pyramidale, radiatum, and oriens but were less concentrated in the alveus. Numerous punctate GJP‐IR elements were observed in all hippocampal layers. Upon EM analysis, GJP‐IR neuronal somata in the stratum pyramidale were found to be, without exception, nonpyramidal neurons as judged by such distinguishing features as their fusiform perikarya, indented nucleus, and well‐developed rough endoplasmic reticulum (RER). Immunostaining within these cells was largely localized to the Golgi apparatus and associated vesicular components. Small, diffusely GJP‐IR cells were identified ultrastructurally as protoplasmic and fibrous astrocytes. Immunostaining within these cells was localized to the Golgi apparatus, RER, and small, ribosomelike bodies 15–25 nm in diameter. Among neuronal processes GJP immunoreactivity was found within dendrites, axons, and axonal terminals. The latter structures contained numerous GJP‐IR vesicles having an average diameter of about 40 nm. A frequent observation indicating some degree of specificity of the anti‐GJP antibody employed here was immunostaining of typical gap junctions between dendrites and, more commonly, between processes of glial cells. Ocassionally, however, GJP‐IR dendrodendritic, axodendritic, and axoaxonic contacts were found that could be considered, at best, as being gap‐junction‐like (gj‐L). In these cases, asymmetric immunostaining of adjacent plasma membranes forming gj‐L structures was not uncommon.These results confirm the existence of gap junctions between dendrites in the rat hippocampus and demonstrate that GJP immunoreactivity on cytoplasmic membranes is restricted either to typical neuronal and glial gap junctions or to gj‐L structures at circumscribed sites of contact between various types of neuronal elements where GJP may contribute to a novel mechanism of neural communication.