bluuebunny/crossref_metadata_2025_split huggingface dataset:
Distribution of cholecystokinin‐like‐immunoreactive neurons in the guinea pig forebrain
Authors: Ciofi Philippe , Tramu Gerard 
Published: January 2005

AbstractThe distribution of cholecystokinin (CCK)‐immunoreactive nerve fibers and cell bodies was studied in the forebrain of control and colchicine‐treated guinea pigs by using an antiserum directed against the carboxyterminus of CCK octapeptide (CCK‐8) in the indirect immunoperoxidase technique. Virtually all forebrain areas examined contained immunoreactive nerve fibers. A dense innervation was visualized in: neocortical layers II‐III, piriform cortex, the medial amygdala, the medial preoptic area, a circumventricular organ‐like structure located at the top of the third ventricle in the preoptic area, the subfornical organ, the posterior bed nucleus of the stria terminalis, the posterior globus pallidus (containing labeled woolly fiber‐like profiles), the ventromedial hypothalamus, the median eminence, and the premammillary nucleus. A moderately dense innervation was visualized elsewhere excepted in the septum and thalamus where labeled axons were comparatively few. Immunoreactive perikarya were abundant in: neocortex (especially layers II‐III), piriform cortex, amygdala, the median preoptic nucleus, the bed nucleus of the stria terminalis, the hypothalamic paraventricular (parvicellular part), arcuate, and dorsomedial (pars compacta) nuclei, the dorsal and perifornical hypothalamic areas, and throughout the thalamus. Areas also containing a moderate number of labeled cell bodies were the medial preoptic area, the globus pallidus, the caudate‐putamen, and the periventromedial area in the hypothalamus. Immunostained perikarya were absent or only occasionally observed in the septum, the suprachiasmatic nucleus, the magnocellular hypothalamoneurohypophyseal nuclei, and the ventral mesencephalon. In the adenohypophysis corticomelanotrophs were labeled in both males and females, and thyrotrophs were labeled in females only.This distribution pattern of CCK‐8 immunoreactivity is compared to those previously recorded in other mammals. This shows that very few features are peculiar to the guinea pig. It is discussed whether some interspecific differences in immunostaining are real rather than methodological.
Cytoarchitectonic atlas of the cochlear nucleus of the chinchilla, Chinchilla laniger
Authors: Morest D. Kent , Hutson K. A. , Kwok S. 
Published: January 2005

AbstractA detailed cytoarchitectonic atlas of the chinchilla cochlear nucleus complex was prepared in the transverse plane with the Nissl method. Subdivisions of the cochlear nucleus were defined on the basis of cell size, cell packing density, and, in some cases, on cytological features of cell types. In general, the chinchilla cochlear nucleus has an organizational plan similar to that described for other mammalian species. As in other rodents, the chinchilla has a large and well‐developed dorsal cochlear nucleus consisting of three distinct layers. The ventral cochlear nucleus consists of two distinct nuclear masses, a posterior nuclear group and an anterior nuclear group, each composed of several subdivisions, which are qualitatively similar to those described for other mammals. Thus it is now possible to compare detailed observations, such as tonotopic maps, in the chinchilla with findings from the analogous cell populations in other mammals, such as the cat with considerable precision. In the chinchilla, three cell groups, previously undescribed in mammals, have been defined and their counterparts in the cat identified.
Intracellular labeling of neurons in the medial accessory olive of the cat: I. Physiology and light microscopy
Authors: Ruigrok T. J. H. , de Zeeuw C. I. , van der Burg J. , Voogd J. 
Published: January 2005

AbstractThis study is the first of three reports on the detailed morphology of horseradish peroxidase injected neurons in the medial accessory olive of the cat.Intracellular, in vivo recordings of olivary cells were made and their response to mesodiencephalic stimulation was tested. In 44 units a short latency action potential could be recorded, which was very suggestive of a monosynaptic excitatory pathway. The short latency response was frequently followed by a long latency (mean 188 msec) or rebound action potential. Recordings were followed by intracellular iontophoresis of horseradish peroxidase.A total of 21 neurons, all located within the medial accessory olive were chosen for morphological analysis. Cells could be divided into two categories on the basis of their overall morphological appearance. Type I cells (n = 5) had sparsely branching dendrites that radiated away from the soma and were usually found in the caudal part of the medial accessory olive. The axon usually originated from the soma. Type II cells (n = 16) were located more rostrally. They had larger cell bodies with dendrites that ramified extensively, forming a globular structure (mean diam. 338 μUm). The axon usually originated from a first order dendrite. No recurrent axon collaterals were observed on either type I or II cells. Both cell types carried long and complex spiny appendages; however, they were most numerous on the second and higher order dendrites of type II cells. Since the soma of these cells is usually not found in the centre of its dendritic field, even if the cell is located in the center area pf the neuropil, it is suggested that the dendritic trees of up to 100 neurons may be intricately interwoven, establishing clusters with intensive intercommunication by means of dendritic gap junctions. The abundance, length and complexity of the spiny appendages suggest an important role in this process, but may also be relevant instruments in enhancing the computational capabilities of these neurons, especially in time sensitive processes.When relating the physiological and the morphological results, it was noted that both type I and type II cells could respond to mesodiencephalic stimulation and were both able to trigger a rebound action potential. No significant correlations were found between cell size and the latency of the rebound.
Intracellular labeling of neurons in the medial accessory olive of the cat: III. Ultrastructure of axon hillock and initial segment and their GABAergic innervation
Authors: De Zeeuw C. I. , Ruigrok T. J. H. , Holstege J. C. , Schalekamp M. P. A. , Voogd J. 
Published: January 2005

AbstractThe gamma‐aminobutyric acid (GABA) synaptic input of identified axons in the cat inferior olive was studied by use of combination of intracellular labeling with horseradish peroxidase and postembedding gold‐immunocytochemistry. With this technique olivary cells were physiologically identified and light microscopically reconstructed, and the horseradish peroxidase reaction product and the immunogold labeling were subsequently simultaneously visualized for electron microscopic investigation with the use of serial ultrathin sections.The axons of cell type I (characterized by dendrites which radiate away from the cell body) originated from the soma, whereas those of type II neurons (characterized by dendritic trees which curve back towards the soma) were derived from a primary dendrite. The axons of olivary neurons stand out by the length of their axon hillock (up to 21 μm) and initial segment (up to 40 μm). The hillock forms various spiny appendages which were located within glomeruli together with dendritic spines of other olivary neurons. Axonal spines of type II neurons were more numerous and complex looking than those of type I. The axonal spines, the shaft of the axon hillock, and the transition between the hillock and initial segment were primarily innervated by GABAergic terminals (65%) but non‐GABAergic terminals (35%) were present as well. The terminals apposed to the axons of type I neurons contacted mainly the axonal shafts, whereas most of the terminals adjacent to the axons of type II neurons established synaptic contacts with the axonal spines. The initial segments were largely devoid of synaptic input. Distally, the initial segment acquired a myelin sheath.
Vasopressin in the brain of the golden hamster: The distribution of vasopressin binding sites and of immunoreactivity to the vasopressin‐related glycopeptide
Authors: Dubois‐Dauphin M. , Pevet P. , Triboilet E. , Dreif'Uss J. J. 
Published: January 2005

AbstractUsing in vitro light microscopic autoradiography and immunocytochemistry, the distribu‐ tion of vasopressin binding sites and that of the vasopressin‐related glycopeptide are described in the brain of golden hamster (Mesocricetus auratus). Vasopressin binding sites and immunoreactive axones were observed in the suprachiasmatic nucleus, in the anterior hypothalamus/median preoptic area, in the medial preoptic nucleus, in the bed nucleus of the stria terminalis, in the habenular complex, in the thalamic paraventricular nucleus, and in the nucleus of the solitary tract.In addition we observed binding sites in regions where no immunoreactivity could be evidenced: the lateral septa1 nucleus, the central amygdaloid nucleus, the subiculum, the dentate gyrus, the anterodorsal and anteroventral thalamic nuclei, the superior colliculus, the vestibular nuclei, and in the prepositus hypoglossal nucleus.In the golden hamster, exogenous vasopressin excites single neurones located in the suprachiasmatic nucleus and induces flank‐marking behavior when microinjected into the preoptic area. Our results provide a morphological basis for similar effects exerted by endogenous vasopressin. A comparison of the present data with those previously described in the rat reveals marked species differences in the brain distribution of vasopressin and of its binding sites.
Development of the anterior olfactory nucleus in normal and unilaterally odor deprived rats
Authors: Brown Jessica L. , Brunjes Peter C. 
Published: January 2005

AbstractThe development of a second order structure in the olfactory pathway, the anterior olfactory nucleus, was examined in both normal rat pups and in subjects which underwent unilateral naris closure on postnatal day 1 (P1)Naris occlusion in neonatal rats produces a constellation of changes within the first relay in the pathway, the olfactory bulb, including a 25% reduction in total volume. Such large changes suggest that higher order structures might also be affected. Anterior olfactory nucleus development was quantified in several ways. Laminar volumes were computed by using serial section planimetry. In control animals differential development was observed, with regions extending most rostrally (e.g., pars externa and pars lateralis)exhibiting the least growth. The anterior olfactory nucleus on the “deprived” side of subjects with a single naris occluded was identical in size to that observed in controls, suggesting that the procedure has little effect on the growth of the structure. Dendritic development within the pars lateralis was examined in control animals at P10, P20, P30, and adults. Developmental increases in numbers of both branches per cell and spines were noted, but mean branch length remained relatively constant. Finally, the effects of naris occlusion on histological patterns of succinate dehydrogenase (SDH) staining and 2‐deoxyglucose uptake within pars lateralis were examined at P20 to test for more subtle effects of naris occlusion. SDH staining was quite similar in deprived and control rats at P20. However, 3H‐2‐DG uptake was decreased in rostral areas of the anterior olfactory nucleus ipsilateral to the deprived olfactory bulb, suggesting that naris closure does affect the structure.
The anterior ectoylvian sulcal auditory field in the cat: II. A horseradisha peroxidase study of its thalamic and cortical connections
Authors: Clarey Janine C. , Irvine Dexter R. F. 
Published: January 2005

AbstractThe thalamic and cortical projections to acoustically responsive regions of the anterior ectosylvian sulcus were determined by identifying retrogradely labelled cells after physiologically guided iontophoretic injections of horseradish peroxidase. The medial division of the medial geniculate nucleus, the intermediate division of the posterior nuclear group, the principal division of the ventromedial nucleus, and the lateroposterior complex were consistently labelled after these injections, although each animal showed slightly different patterns of labelling. The suprageniculate nucleus and the lateral and medial divisions of the posterior nuclear group were also labelled in most experiments. The cortex of the suprasylvian sulcus was the most consistently and densely labelled cortical region; each experiment showed a slightly different pattern of labelling throughout the suprasylvian sulcus, with an overall tendency for greater labelling in the ventral (lateral) bank of the middle region of the sulcus. Other cortical regions labelled less consistently included the anterior ectosylvian sulcus itself, the insular cortex of the anterior sylvian gyrus, and the posterior rhinal sulcus. In three experiments the contralateral cortex was examined and a small number of labelled cells was located in the anterior ectosylvian and suprasylvian sulci.Input from extralemniscal auditory thalamus is compatible with previously described auditory response properties of anterior ectosylvian sulcus neurons. The results also confirm the presence of input from visual and multimodal regions of thalamus and cortex, and therefore support claims of overlap of modalities within the sulcus. This overlap, as well as input from motor regions, suggests that the anterior ectosylvian sulcal field serves a sensorimotor role.
Mosaic organization of the hippocampal neuroepithelium and the multiple germinal sources of dentate granule cells
Authors: Altman Joseph , Bayer Shirley A. 
Published: January 2005

AbstractThis study deals with the site of origin, migration, and settling of the principal cell constituents of the rat hippocampus during the embryonic period, The results indicate that the hippocampal neuroepithelium consists of three morphogenetically discrete components—the Ammonic neuroepithelium, the primary dentate neuroepithelium, and the fimbrial glioepithelium—and that these are discrete sources of the large neurons of Ammon's horn, the smaller granular neurons of the dentate gyrus, and the glial cells of the fimbria.The putative Ammonic neuroepithelium is marked in short‐survival thymidine radiograms by a high level of proliferative activity and evidence of interkinetic nuclear migration from day E16 until day E19. On days E16 and E17 a diffuse band of unlabeled cells forms outside the Ammonic neuroepithelium. These postmitotic cells are considered to be stratum radiatum and stratum oriens neurons, which are produced in large numbers as early as day E15. A cell‐dense layer, the incipient stratum pyramidale, begins to form on day E18 and spindle‐shaped cells can be traced to it from the Ammonic neuroepithelium. This migratory band increases in size for several days, then declines, and finally disappears by day E22. It is inferred that this migration contains the pyramidal cells of Ammon's horn that are produced mostly on days E17 through E20.The putative primary dentate neuroepithelium is distinguished from the Ammonic neuroepithelium during the early phases of embryonic development by its location, shape, and cellular dynamics. It is located around a ventricular indentation, the dentate notch, contains fewer mitotic cells near the lumen of the ventricle than the Ammonic neuroepithelium, and shows a different labeling pattern both in short‐survival and sequential‐survival thymidine radiograms. By day E18, the reduced primary dentate neuroepithelium is surrounded by an aggregate of proliferative cells; this is the secondary dentate matrix. On the subsequent days spindle‐shaped cells that have retained their proliferative capacity migrate from the progressively receding secondary dentate matrix to the dentate gyrus itself. The latter, representing a tertiary germinal matrix, becomes highly active during the perinatal period.The putative fimbrial glioepithelium is situated between the primary dentate neuroepithelium and the tip of the hippocampal rudiment. Observations in methacrylate sections and thymidine radiograms suggest that the cells of this germinal matrix, unlike typical neuroepithelial cells, do not undergo interkinetic nuclear migration. The fimbrial glioepithelium is clearly present by day E16, two days before the fimbria becomes a distinct fiber tract. As the fimbria emerges, cells of the putative glial matrix migrate into it.
Migration and distribution of two populations of hippocampal granule cell precursors during the perinatal and postnatal periods
Authors: Altman Joseph , Bayer Shirley A. 
Published: January 2005

AbstractMethacrylate‐embedded sections and short‐survival thymidine radiograms of the hippocampal dentate gyrus were examined in perinatal and postnatal rats in order to trace the site of origin and migration of the precursors of granule cells and study the morphogenesis of the granular layer. The densely packed, spindle‐shaped cells of the secondary dentate matrix (a derivative of the primary dentate neuroepithelium) stream in a subpial position towards the granular layer of the internal dentate limb during the perinatal and early postnatal periods. By an accretionary process, the crest of the granular layer forms on day E21 and on the subsequent days the granular layer of the internal dentate limb expands progressively in a lateral direction. Granule cells differentiation, as judged by the transformation of polymorph, darkly staining small cells into rounder, lightly staining larger granule cells, follows the same gradient from the external dentate limb to the internal dentate limb. The secondary dentate matrix is in a process of dissolution by day P5. This matrix is the source of what will later become the outer shell of the granular layer composed of early generated granule cells. The thicker inner shell of the granular layer, formed during the infantile and juvenile periods, derives from an intrinsic, tertiary germinal matrix. On day E22, the dentate migration of the secondary dentate matrix becomes partitioned into two components: (a) the subpial component of extradentate origin, referred to in this context as the first dentate migration, and (b) the second dentate migration. The latter is distributed in the basal polymorph layer throughout the entire dentate gyrus and is henceforth recognized as the tertiary dentate matrix. The tertiary dentate matrix is prominent between days P3 and P10. It is postulated that the great increase in granule cell population during the infantile period is principally due to cells derived from this intrinsic matrix of the dentate gyrus. Between days P20 and P30 the tertiary dentate matrix disappears in the basal polymorph layer and henceforth proliferative cells become largely confined to the subgranular zone at the base of the granular layer. The subgranular zone is the source of granule cells produced during the juvenile and adult periods.
Medullary projection of nonaugmenting inspiratory neurons of the ventrolateral medulla in the cat
Authors: Otake Kazuyoshi , Sasaki Hiroshi , Ezure Kazuhisa , Manabe Motomu 
Published: January 2005

AbstractIn Nembutal‐anesthetized, immobilized, and artificially ventilated cats, we studied the morphological characteristics of inspiratory neurons with nonaugmenting firing patterns. HRP was injected intracellularly into a total of 22 neurons of the Bötzinger complex (BÖT) and the ventral respiratory group (VRG). In 20 cases somata with their axonal trajectories were stained, and in two cases only axons were stained. None of the neurons stained could be antidromically activated by stimulation of the cervical cord. The somata of 20 neurons were located in the vicinity of the nucleus ambiguus or the retrofacial nucleus (RFN) between 600 μm and 2,800 μm caudal to the rostral end of the RFN. Their axons could be traced for a distance of several millimeters on the side of the somata, and showed various projection patterns. According to these projection patterns, the 20 neurons were tentatively classified into four groups: A (8/20), B (4/20), C (6/20), and motoneurons (2/20). Group A neurons gave off extensive axon collaterals that arborized and distributed boutons predominantly in the BÖT and the VRG areas. Group B neurons had less extensive axon collaterals with various projection patterns, projecting rarely to the BÖT or the VRG area. Group C neurons sent their stem axons, without issuing any axonal collaterals, to the contralateral side in five cases and to the ipsilateral pons in one case. The two motoneurons had axons leaving the brainstem without any intramedullary collaterals. Thus, the nonaugmenting inspiratory neurons showed morphological variations, which may play different roles in neural control of respiration.
Identification of spinal neurons in the embryonic and larval zebrafish
Authors: Bernhardt Robert R. , Chitnis Ajay B. , Lindamer Laurie , Kuwada John Y. 
Published: January 2005

AbstractPrevious studies indicated that the developing fish spinal cord was a simple system containing a small number of distinguishable neuronal cell types (Eisen et al., Nature 320:269–271, '86; Kuwada, Science, 233:740–746, '86). To verify this we have characterized the cellular anatomy of the spinal cord of developing zebrafish in order to determine the number, identities, and organization of the spinal neurons. Spinal neurons were labeled by intracellular dye injections, application of an axonal tracer dye to all or subsets of the axonal tracts, and application of antibodies which recognize embryonic neurons. We found that nine classes of neurons could be identified based on soma size and position, pattern of dendrites, axonal trajectory, and time of axonogenesis. These are two classes of axial motor neurons, which have been previously characterized (Myers, J. Comp. Neurol. 236:555–561, '85), one class of sensory neurons, and six classes of interneurons. One of the interneuron classes could be subclassified as primary and secondary based on criteria similar to those used to classify the axial motor neurons into primary and secondary classes.The early cord (18–20 hours) is an extremely simple system and contains approximately 18 lateral cell bodies per hemisegment, which presumably are post‐mitotic cells. By this stage, five of the neuronal classes have begun axonogenesis including the primary motor neurons, sensory neurons, and three classes of interneurons. By concentrating on these early stages when the cord is at its simplest, pathfinding by growth cones of known identities can be described in detail. Then it should be possible to test many different mechanisms which may guide growth cones in the vertebrate central nervous system (CNS).
Long‐term survival and sprouting in culture by motoneurons isolated from the spinal cord of adult frogs
Authors: Kuffler Damien P. 
Published: January 2005

AbstractMotoneurons of adult frog spinal cord have been retrogradely labeled with the carbocyanine derivative diI. Spinal cords were then dissociated and the labeled motoneurons partially purified by centrifugation over a bovine serum albumin (BSA) density gradient. The resulting cell suspension was plated on a substrate of innervated muscle extracellular matrix (ECM) to which the motoneurons attached and extended processes. Labeled adult motoneurons survived for more than 4 weeks in a defined medium in the absence of added serum or growth factors. These cultures of adult motoneurons provide a favorable preparation for studying molecular factors that influence process outgrowth and synapse formation.