bluuebunny/crossref_metadata_2025_split huggingface dataset:
Distribution of β‐nerve growth factor receptors in the human basal forebrain
Authors: Allen Shelley J. , Dawbarn David , Spillantini Maria G. , Goedert Michel , Wilcock Gordon K. , Moss Timothy H. , Semenenko Frances M. 
Published: January 2005

AbstractThe distribution of neurons expressing the receptor for β‐nerve growth factor has been examined immunohistochemically in serial coronal sections of basal forebrain from aged normal human subjects. Neurons expressing the receptor were observed in the nucleus of the diagonal band of Broca and in the anterior, the intermediate, and the posterior portions of the nucleus basalis of Meynert. Neurons could also be seen in the medial septal nucleus and embedded in myelinated fibre tracts such as those of the external capsule, cingulum, medullary laminae of the globus pallidus, ansa penduncularis, ansa lenticularis, and anterior commissure. In situ hybridization with a 35S cDNA probe to the human β‐nerve growth factor receptor confirms a neuronal location as the site of synthesis of β‐nerve growth factor receptors in the nucleus basalis of Meynert in a fifth brain. A high percentage of Nissl‐stained hyperchromic magnocellular neurons expressed the receptor for β‐nerve growth factor, suggesting that most neurons in the human cholinergic magnocellular basal forebrain system express these receptors.Recent data suggest that β‐nerve growth factor functions as a neurotrophic factor in basal forebrain cholinergic neurons. In Alzheimer's disease there is known to be a reduction in cholinergic function and an apparent loss of neurons in the cholinergic nucleus basalis of Meynert. For this reason we have examined the distribution of receptors for β‐nerve growth factor in the normal human basal forebrain in order to form a basis for comparison to those with Alzheimer's disease.
Distribution of corticotropin‐releasing factor in the cerebellum and precerebellar nuclei of the cat
Authors: Cummings Sharon L. 
Published: January 2005

AbstractThe present study analyzes the distribution of corticotropin‐releasing factor‐immunoreactive (CRF‐IR) fibers and neuronal cell bodies within the cerebellum and brainstem, respectively, of the cat. Within the cerebellum, CRF is present in climbing fibers, mossy fibers, and a population of varicose fibers which traverses the lower molecular layer. CRF‐IR fibers are present throughout all lobules of the cat cerebellar cortex, though the density and immunostaining intensity of each fiber system vary. Bands of intensely immunoreactive climbing fibers are prominent within the vermis, intermediate cortex, and crus II. Bands of intensely immunoreactive mossy fiber terminals accompany the climbing fiber bands within the vermis. Collaterals of climbing and mossy fibers contribute to a beaded fiber plexus localized to the Purkinje cell layer. Varicose fibers containing CRF immunoreactivity are present in all deep cerebellar nuclei. CRF‐IR neuronal cell bodies are prominent within several brainstem nuclei known to project to the cerebellum: all divisions of the inferior olivary complex, the lateral reticular nucleus, paramedian reticular nucleus, gigantocellular reticular nucleus, raphe nuclei, perihypoglossal complex, medial and inferior vestibular nuclei and cell groups f and x, locus ceruleus, and nucleus subceruleus. This study confirms and extends a previous study of CRF distribution within cerebellar afferent systems of the cat (Cummings et al.: J. Neurosci. 8:543–554, '88) and compares this distribution with previous descriptions in other species. The ubiquitous distribution of CRF throughout the cat cerebellum suggests a primary role for this peptide in signal transduction.
Catecholamine‐containing neurons in the sheep brainstem and diencephalon: Immunohistochemical study with tyrosine hydroxylase (TH) and dopamine‐β‐hydroxylase (DBH) antibodies
Authors: Tillet Yves , Thibault Jean 
Published: January 2005

AbstractThe present study describes the distribution and morphological characteristics of neurons and nerve fibers containing the catecholamine‐synthesizing enzymes, tyrosine hydroxylase and dopamine‐β‐hydroxylase, in the sheep brainstem and diencephalon on the basis of immunohistochemical procedures. Neurons and fibers were considered to be dopaminergic if they showed antityrosine hydroxylase immunoreactivity, without corresponding anti‐dopamine‐β‐hydroxylase immunoreactivity. The structures labeled with both antisera were considered noradrenergic or adrenergic. The distribution of catecholaminergic neurons corresponds to that described by other authors with similar methods in the rat and in primates. The noradrenergic neurons belong to cell groups A1 to A7 and the dopaminergic neurons to cell groups A8 to A15. In almost all studied areas, the catecholaminergic innervation is similar to that observed in the other species. However, the central catecholaminergic systems of the sheep showed some specific characteristics: (1) groups A3 and A4, described in the rat, were not found, (2) group A14 contains fewer neurons than in the rat, (3) group A15 does not contain a dorsal but only a ventral portion, (4) there is a larger dispersion of neurons within each group, especially A6 and A7, than in rodents, and (5) there is a larger noradrenergic innervation of the catecholaminergic groups than in the other species.
Amygdaloid efferents through the stria terminalis in the rat give origin to zinc‐containing boutons
Authors: Pérez‐Clausell Jeús , Frederickson Christopher J. , Danscher Gorm 
Published: January 2005

AbstractMany regions of the basal forebrain are innervated by zinc‐containing axonal boutons. In the present work, the lesion/degeneration method, coupled with histochemical staining for zinc‐containing boutons, was used to determine the origins and efferent pathways of these zinc‐containing projections to the basal forebrain.Knife cuts of the stria terminalis or extensive electrolytic lesions of the amygdala resulted in the bleaching of the staining for zinc (Timm stain) and terminal degeneration (Fink‐Heimer method) ipsilaterally in the following areas: granule cell layer of the accessory olfactory bulb, shell of nucleus accumbens, bed nucleus of the stria terminalis, striohypothalamic nucleus, retrochiasmatic area, ventromedial hypothalamic nucleus (in the cell‐sparse shell), medial tuberal nucleus, terete hypothalamic nucleus, and ventral premammillary nucleus. Small lesions made with ibotenic acid in the posteromedial part of the amygdalohippocampal area caused bleaching of the stain for zinc in the accessory olfactory bulb, in the medial zone of the bed nucleus of the stria terminalis, and in the ventral premammillary nucleus. Lesions in either the ventral subiculum or the anterolateral part of the amygdalohippocampal area caused bleaching in the ventromedial hypothalamic nucleus. Lesions in the hippocampus or in the neocortex did not produce bleaching of the stain for zinc in the above‐mentioned terminal fields.The present results agree with previous studies on amygdaloid efferents and suggest that neurons in the amygdalhippocampal area and, possibly, in the ventral subiculum give origin to zinc‐containing boutons.
Neuronal localisation of neuropeptide Y gene expression in rat brain
Authors: Morris Brian J. 
Published: January 2005

AbstractThe cellular location of Neuropeptide Y (NPY) synthesis in rat brain is identified by using in‐situ hybridisation histochemistry. The results show that NPY mRNA is widely distributed through the rat brain, although the levels of NPY mRNA are surprisingly low. There is a large degree of variation in the content of NPY mRNA in different regions. The highest cellular levels of NPY mRNA are found in the arcuate nucleus of the hypothalamus, in the cerebral cortex, and in the hilar region of the hippocampus. In general, the distribution of perikarya containing NPY mRNA corresponds to the reported distribution of perikarya containing NPY‐immunoreactivity. However, NPY mRNA was detected in the majority of the perikarya in the reticular nucleus of the thalamus, an area not previously known to contain NPY neurones. In many areas of the forebrain the distribution of NPY mRNA parallels that of somatostatin mRNA, supporting suggestions of their coexistence. The ability to detect NPY mRNA at the cellular level should be of considerable use in dynamic studies of the activity of NPY neurones.
Distribution of muscarinic acetylcholine receptors on processes of isolated retinal cells
Authors: Townes‐Anderson Ellen , Vogt Brent A. 
Published: January 2005

AbstractBinding of propylbenzilylcholine mustard, a muscarinic acetylcholine receptor antagonist, to isolated retinal cells was examined with light microscopic autoradiography. Dissociation of the adult tiger salamander retina yielded identifiable rod, cone, horizontal, bipolar, amacrine/ganglion, and Müller cells. Preservation of fine structure was assessed with conventional electron microscopy. For all cell types, the plasmalemma was intact and free of adhering debris; in addition, presynaptic ribbon complexes were present in photoreceptor and bipolar axon terminals indicating that synaptic structures were retained. Specific binding to cell bodies and processes was analyzed separately by using morphometric and statistical techniques. The highest grain densities occurred on processes of amacrine/ganglion cells and axons and 2° and 3° dendrites of bipolar neurons. Bipolar cells, however, seemed to be a heterogeneous population because there was great variation in the density of binding sites on both their axons and distal dendrites. Intermediate levels of binding were found on bipolar 1° dendrites and horizontal cells. No specific binding was detected on Müller cells and most parts of photoreceptors. Comparisons between cells showed that grain densities were similar for bipolar axons and amacrine/ganglion cell processes but bipolar dendrites were richer in binding sites than horizontal cell dendrites. Thus, muscarinic receptors in the salamander retina are located on amacrine/ganglion, bipolar, and horizontal cells and primarily confined to the processes which compose the two synaptic layers. In the inner plexiform layer, muscarinic receptors reside on processes from all three inner retinal neurons; in the outer synaptic layer, receptors are only on second‐order cells and are more numerous along bipolar than horizontal cell dendrites.
Morphology of single primary vestibular afferents originating from the horizontal semicircular canal in the cat
Authors: Sato Fumi , Sasaki Hiroshi , Ishizuka Norio , Sasaki Sei‐Ichi , Mannen Hajime 
Published: January 2005

AbstractThe central projections of physiologically characterized vestibular nerve fibers originating from the horizontal semicircular canal were studied in the vestibular nuclei of adult cats after intracellular staining with horseradish peroxidase (HRP). First, primary nerve fibers were physiologically classified as regular or irregular types on the basis of the regularity of the spontaneous discharge pattern. Then, these two types of fibers were morphologically analyzed and compared following HRP intraaxonal injection. The two types of axons showed a basically similar trajectory in the four major vestibular nuclei. They bifurcated into an ascending and a descending branch in the ventrolateral part of the lateral vestibular nucleus (LVN). The ascending branch extended rostrally and gave off one or two collaterals in the superior vestibular nucleus (SVN), although some of the ascending branches further ran rostrally into the cerebellum. The collaterals, while running medially, gave rise to fine terminal branches with en passant boutons in the SVN, and further coursing caudally, they entered the rostral part of the medial vestibular nucleus (MVN). The descending branch, while running caudally in the lateral part of the LVN and the inferior vestibular nucleus (IVN), gave off several thick collaterals to the MVN and extensive terminals were present in the IVN and MVN. In each primary axon, about one‐third of the total terminal boutons were distributed in each of the SVN, the MVN, and the IVN. In contrast to this similarity of the overall axonal trajectory within the vestibular nuclei, both types of axons exhibited several marked differences in diameter and in the mode of terminal arborization. In almost every part of the ramification, the irregular‐type fibers were thicker than the regular‐type fibers. In the regular‐type axons, many small terminal boutons (mean size, 2.4 × 1.4 μm, N = 2,739) were located in close proximity (100–150 μm) to the parent collateral. In the irregular‐type axons, slightly larger terminal boutons (mean size, 3.0 × 1.7 μm, N = 1,287), were spread more widely (200–300 μm) around their collaterals. These clear morphological differences between the regular‐type and the irregular‐type terminal axons were consistently observed in any vestibular nucleus.
Parasagittal organization of the rat cerebellar cortex: Direct comparison of purkinje cell compartments and the organization of the spinocerebellar projection
Authors: Gravel Claude , Hawkes Richard 
Published: January 2005

AbstractRetrograde and anterograde transport of tracers, electrophysiological recording, somatotopic mapping, and histochemical and immunological techniques have all revealed a parasagittal parcellation of the cerebellar cortex, including its efferent and many of its afferent connections. In order to establish whether the different compartments share a common organizational plan, a systematic comparative analysis of the patterns of parasagittal zonation in the cerebellar cortex of the rat has been undertaken, by using the parasagittal compartmentation of zebrin I+ and zebrin I‐Purkinje cells as revealed by monoclonal antibody Q113 as a reference frame. The distribution of mossy fiber terminals originating from the lower thoracic‐higher lumbar spinal cord was compared to the distribution of zebrin I bands. Three‐dimensional reconstructions from alternate frontal sections processed either for the anterograde transport of tracer or for zebrin I immunoreactivity reveal that the limits of the spinocerebellar terminal fields in the granular layer correlate well with the boundaries of some, but not all, zebrin I compartments in the molecular layer above. This leads to a subdivision of the zebrin I compartments into spinal receiving and spinal nonreceiving portions. In lobules II and VIII, the spinocerebellar terminal fields assume different positions relative to the zebrin I compartments in the ventral compared to the dorsal faces. Thus, each longitudinal compartment may be further divided transversely into subzones, each receiving a specific combination of mossy fiber afferents. The further subdivision of zebrin I compartments by mossy fiber terminal fields increases the resolution of the topography to such a point that anatomical compartment widths become compatible with the width of the microzones and the patches identified by electrophysiological methods.
Maturation of the corpus callosum of the rat: II. Influence of thyroid hormones on the number and maturation of axons
Authors: Gravel Claude , Sasseville Rachel , Hawkes Richard 
Published: January 2005

AbstractQuantitative electron microscopy has been used to study the number of callosal axons in the corpus callosum of normal and hypothyroid rats during postnatal development. At birth, the normal corpus callosum contains 4.4 × 106 axons. This number increases to 11.4 × 106 by 5 days of age (P5) and then, in contrast to cats and primates, remains constant until at least P60, the oldest age examined. The number of axons in the corpus callosum of hypothyroid animals is not significantly different from the values observed in normal rats at all ages studied, although the callosal axons of hypothyroid rats remain structurally immature. As extensive elimination of callosal axons has been shown to occur in normal rats past P5, we conclude that new callosal processes grow through the corpus callosum past this age that compensate numerically for the loss. Moreover, as the number of callosally projecting neurons seems to be higher in hypothyroid rats than in normal controls, it seems that the constant axon number derives from more parent neurons, and thus that there are more axon collaterals per callosal neuron in a normal animal than in a hypothyroid one. Taken together, these data indicate that although hypothyroidism does not alter the total number of callosally projecting axons, it interferes with the normal processes that define or sculpt the projection fields, thereby leading to a numerically normal projection with abnormal topography.
Cells of origin of the spinohypothalamic tract in the rat
Authors: Burstein Rami , Cliffer Kenneth D. , Giesler Glenn J. 
Published: January 2005

AbstractWe recently demonstrated that large numbers of neurons in the spinal cord of rats project directly to the hypothalamus. In the present study, we used the retrograde tracer Fluoro‐Gold (FG) to examine this projection more completely. In the first series ofss studies, we attempted to label the entire population of spinal cord neurons that project to the hypothalamus. Injections that virtually filled the hypothalamus on one side without spreading into any other diencephalic area labeled a large number of neurons (estimated to be more than 9,000 in the case with the most neurons labeled) bilaterally at all levels of the spinal cord. Approximately 60° of the labeled neurons were contralateral to the injection. The greatest number of labeled neurons was found within the deep dorsal horn. Many were also found within the lateral spinal nucleus, the superficial dorsal horn, and the gray matter surrounding the central canal. A small number of labeled cells was located in the intermediate zone and ventral horn of the spinal gray matter. Labeled neurons were distributed bilaterally within the sacral parasympathetic nucleus and trigeminal nucleus caudalis.Injections of FG restricted to the medial hypothalamus labeled neurons within the spinal cord in a distribution similar to that produced by injections that filled the hypothalamus. However, fewer neurons were labeled in the spinal cord (estimated to be more than 6,200) and trigeminal nucleus caudalis.Injections of FG restricted to the lateral hypothalamus also labeled fewer neurons (approximately 3,300) than did injections that filled the hypothalamus. In these cases, also, the pattern of labeled neurons within the spinal cord was similar to that produced by injections within either medial or both medial and lateral hypothalamus. However, few neurons were labeled in the sacral parasympathetic nucleus following injections into the lateral hypothalamus.These findings show the distribution of a large number of spinal cord neurons that project directly to medial or lateral hypothalamic regions that are involved in autonomic, neuroendocrine, and emotional responses to somatosensory stimulation, including painful stimuli.
Olivocerebellar fiber maturation in normal and lurcher mutant mice: Defective development in lurcher
Authors: Heckroth John A. , Goldowitz Dan , Eisenman Leonard M. 
Published: January 2005

AbstractOlivocerebellar fiber maturation was examined in normal and lurcher mutant mice between postnatal day 5 (P5) and P15, using the anterograde transport of wheat germ agglutinin‐horseradish peroxidase (WGA‐HRP) from the inferior olive. Immunocytochemistry for the Purkinje cell marker PEP‐19 was used to demonstrate Purkinje cell development in the same material. In mutant and normal animals, a regional developmental variation is observed such that, when compared at a given age, cortex lining the vermal fissures appears developmentally advanced over cortex in the cerebellar hemispheres. In the primary fissure of the normal animals, the first recognizable Purkinje cell dendrites appear on P6, and the olivocerebellar fibers first enter the climbing stage of their development on P9. In lurcher animals Purkinje cell development proceeds on this schedule, but olivocerebellar fibers are never observed to enter the molecular layer. These afferents maintain dense perisomatic nests around Purkinje cells, even in P13‐15 lurchers. Examination of P14 lurchers by transmission electron microscopy indicates that the olivocerebellar fibers form synapses on Purkinje cell somatic spines and that the basket cell axons fail to form their typical perisomal nests around Purkinje cells. In addition, parallel fibers can be observed to synapse on dendritic spines on the Purkinje cell primary dendrites. We interpret these results as indicating a recognition defect between olivocerebellar fibers and Purkinje cell dendrites. An analysis of this defect in lurcher may reveal how the normal transformation of olivocerebellar fibers, from perisomal to dendritic terminals, is achieved.
Postnatal changes in the density and distribution of neurotensin‐like immunoreactive fibers in the mediodorsal nucleus of the thalamus in the rat
Authors: Ray James P. , Price Joseph L. 
Published: January 2005

AbstractA previous report (Inagaki et al., Brain Res. 260:143‐146, '83) suggested that the peptide neurotensin is contained in neurons of the piriform cortex that project to the mediodorsal thalamic nucleus MD in young rats. To confirm this, we have studied the distribution of neurotensin‐like immunoreactive NTIR fibers in MD during development, using three antisera directed at different parts of the neurotensin molecule Emson et al., J. Neurochem. 38:992‐999, 82. In adult rats, NTIR fibers in MD are sparse. They are located mostly at the medial edge of MD and in the adjacent midline thalamic nuclei, with a few poorly stained NTIR fibers in the central part of MD. In contrast, during the first postnatal week, both the medial and central portions of MD stain heavily for neurotensin. The density of NTIR fibers in MD then progressively decreases until the density typical of adult rats is reached, at about 5 weeks. Changes in the distribution of NTIR fibers in MD also occur. In 7‐day‐old rats, the patches of NTIR fibers in the medial and central parts of MD are contiguous, but by 10 days a sparsely immunoreactive zone forms between them. With maturation, this zone enlarges as the density of neurotensin staining decreases, until the medial contingent of NTIR fibers reaches its adult position at the medial edge of MD.From a comparison of the distribution of NTIR cells with that of cells that can be retrogradely labeled from MD or the midline thalamus, the probable source of the NTIR fibers to the central part of MD is in the deep layer of the piriform cortex, while the NTIR fibers to the medial edge of MD and the midline nuclei may arise from the preoptic region and the medial amygdala. In neonatal rats, neurons are found in the piriform cortex, the preoptic region, and the medial amygdala, which can be double‐labeled both for neurotensin and with a retrograde tracer injected into MD and the midline thalamus. Projections of the preoptic region to the thalamus have a distribution similar to that of the medial population of NTIR fibers, whereas the distribution of piriform cortical afferents in central MD matches the central patch of NTIR fibers.