bluuebunny/crossref_metadata_2025_split huggingface dataset:
Vasopressin in the brain of a desert hibernator, the jerboa (Jaculus orientalis): Presence of sexual dimorphism and seasonal variation
Authors: Lakhdar‐Ghazal N. , Dubois‐Dauphin M. , Hermes M. L. H. J. , Buijs R. M. , Bengelloun W. A. , Pévet P. 
Published: January 2005

AbstractThe distribution of vasopressin innervation in the brain of the jerboa (Jaculus orientalis)was investigated, with special attention to sex differences and seasonal variations. Vasopressin perikarya were observed in the paraventricular and supraoptic nuclei, the suprachiasmatic nucleus, the periventricular nucleus, the medial preoptic area, the bed nucleus of the stria terminalis, and the medial amygdaloid nucleus. In addition, vasopressin cell bodies were observed in the ventral retrochiasmatic area. After treatment with colchicine, vasopreasin perikarya were also observed around the organum vasculosum laminae terminalis, in the medial diagonal band of Broca, and in the dorsal medial preoptic nucleus.Vasopressin fibers were also found to be more widespread in the jerboa brain than in other rodents. Fibers were observed in the medial diagonal band of Broca, the stria medullaris, the tuber cinerum, the area postrema, the medial vestibular nucleus, and the dorsal motor nucleus of the vagus.Sexual dimorphism and seasonal variation in vasopressin immunoreactivity were observed in areas that not only showed a testosterone‐dependent vasopressin innervation in other rodents but also in the paratenial and mediodorsal thalamic nuclei, the tuber cinerum, the suprarnarnmillary complex, the zona incerta, the interpeduncular complex, and the dorsal and medial raphe nuclei. A denser vasopressin innervation was observed in spring/summer (sexual active period) than in autumn. Numerous brain structures contained vasopressin receptors (cerebral cortex, hypothalamus, substantia nigra, dentate gyrus, thalamic nuclei, superior colliculus, dorsal cochlear nucleus, and cerebellum); no sex‐ or season‐related differences were observed.These data indicate a high level of vasopressin in the jerboa brain, which may reflect an adaptation to its harsh bioclimatic environment. © 1995 Wiley‐Liss, Inc.
Reconstitution of the rat olfactory epithelium after methyl bromide‐induced lesion
Authors: Schwob James E. , Youngentob Steven L. , Mezza Renee C. 
Published: January 2005

AbstractThe olfactory epithelium and its neuronal population are known to have a substantial capacity to recover after either direct injury or damage to the olfactory nerve. However, the mechanisms underlying that capacity for recovery, and indeed the limits on the recovery process, are not well understood. The aim of this study is to describe in detail the way in which the olfactory epithelium reconstitutes after direct injury. Adult male rats were exposed to 330 ppm methyl bromide (MeBr) gas for a single 6—hour period. The exposure destroys all of the neurons and sustentacular cells in over 95% of the olfactory epithelium of food‐restricted rats and in over 90% of the epithelium in ad‐libitum‐fed rats of the same weight, yet substantial recovery of the olfactory epithelium occurs. In response to the lesion, cellular proliferation increases markedly beginning between 24 and 48 hours, peaks at 1 week, and persists at levels higher than the control level for more than 4 weeks after MeBr exposure. Even though proliferation accelerates promptly, the beginning of neuronal reconstitution is delayed; only few immature neurons are observed 3 days after the lesion, yet they reappear in large numbers by the end of the first week. The first mature neurons emerge between 7 and 14 days after lesion and increase to near normal numbers by 4–6 weeks. In association with the restoration of neuronal population, basal cell proliferation returns to control levels between 4 and 6 weeks after damage. Likewise, sustentacular cells, identifiable by anticytokeratin 18 labeling, reappear rapidly and reform a distinct lamina in the superficial aspect of the epithelium. They closely resemble their counterparts in control epithelium with regard to disposition and shape by 3 weeks after lesion and with regard to expression of olfactory‐specific cytochrome P450s by 8 weeks. Thus, most areas of the epithelium are restored to a near normal appearance and cellular composition by the end of 8 weeks, suggesting that the MeBr paradigm for lesioning epithelium offers significant advantages over techniques such as Triton X‐100 or ZnSO4 irrigation. However, not all measures of epithelial status are normal even at 8 weeks. Immature neurons remain slightly more numerous than normal at this time. Furthermore, some areas of the olfactory epithelium do not recover after MeBr lesion and are replaced by respiratory epithelium. By documenting the events and the extent of olfactory epithelial reconstitution after direct injury, the present results serve as a foundation for future studies designed to identify the mechanisms underlying epithelial recovery and the difference between areas of epithelium that reconstitute fully after lesion and those where the recovery process fails. © 1995 Wiley‐Liss, Inc.
Increase in α‐CGRP and GAP‐43 in aged motoneurons: A study of peptides, growth factors, and ChAT mRNA in the lumbar spinal cord of senescent rats with symptoms of hindlimb incapacities
Authors: Johnson Hans , Mossberg Karin , Arvidsson Ulf , Piehl Fredrik , Hökfelt Tomas , Ulfhake Brun 
Published: January 2005

AbstractSprague‐Dawley rats develop progressive motor dysfunctions during the third year of life. We use this as a model to examine possible neuronal mechanism(s) that may cause motor impairments occuring during aging.In this study we have used indirect immunofluorescence histochemistry (IF) and in situ hybridization histochemistry (ISH) to study quantitatively and qualitatively the staining pattern and mRNA expression of calcitonin gene‐related peptide (α‐CGRP), growth‐associated protein 43 (GAP‐43), and acidic fibroblast growth factor (aFGF) in spinal lumbar motoneurons of young adult (2–3 months) and aged (30 months) Sprague‐Dawley rats. In addition, mRNAs encoding choline acetyltrimsferase (ChAT), β‐CGRP, and cholecystokinin (CCK) were analyzed.All aged rats used in this study disclosed symptoms of hindlimb incapacity, ranging from mild weight‐bearing insufficiency to paralysis of the hind limbs. The symptoms were confined to the musculature of the hindlimb and hip regions. Only a small number (∼ 15%) of the large motoneurons that innervate the hindlimb muscles were lost in those aged rats that had clinical symptoms of hindlimb motor incapacities. The remaining motoneurons expressed ChAT mRNA at levels similar to those of Young adult rats. The vast majority of these motoneurons showed increased mRNA levels for α‐CGRP and GAP‐43. Aged motoneurons contained more CGRP like immunoreactivity (LI), but the number of immunoreactive neurons was smaller than in adult rats. GAP‐43‐LI could be detected in motoneurons in aged, but not in adult, rats. GAP‐43‐LI was always colocalized with CGRP‐LI in aged motoneurons. Studies of individual aged rats revealed that the increase of GAP‐43 mRNA‐positive coll bodies occurred in cases with the most severe clinical symptoms, whereas the increase in α‐CGRP was even evident in rats with mild symptoms. No alterations in content of aFGF‐LI or aFGF mRNA could be detected in the aged rat, and the content of CCK and β‐CGRP mRNAs was also normal. The usefulness of this rat model for studies of neuromuscular aging and possible functional roles for GAP‐43 and CGRP in plastic and regenerative processes during aging are discussed. © 1995 Wiley‐Liss, Inc.
AMPA‐selective glutamate receptor subtype immunoreactivity in the aged human hippocampal formation
Authors: Ikonomovic Milos D. , Sheffield Roxanne , Armstrong David M. 
Published: January 2005

AbstractIt has been hypothesized that, in Alzheimer's disease, glutamate‐mediated excitotoxicity contributes to the degeneration of selected populations of neurons. In the present study, immunocytochemical techniques were used to determine the distribution and anatomical features of GluR1‐ and GluR2/3‐immunolabeled cell bodies and processes within the hippocampal formation of normal (i.e., no pathology) elderly humans. The results of this study provide an essential baseline with which to compare the expression and distribution of glutamate receptor subunits within the brains of patients with Alzheimer's disease.With respect to GluR1 immunoreactivity, the molecular layer of the dentate gyrus displays the most intense immunolabeling of any hippocampal structure. Contributing to this intense labeling are apical dendrites that arise from neurons within the adjacent granule cell layer. Interestingly, GluR1‐labeled neurons account for a relatively small percentage of the total number of neurons as revealed by Nissl staining in the granule cell layer. In contrast, GluR2/3‐labeled neurons are densely distributed throughout the granule cell layer, yet they provide relatively few processes to the adjacent molecular layer compared to GluR1‐positive processes.GluRl labeling is also prominent within the CA fields of Ammon's horn, with CA2 > CA3 > CA1 ≥ CA4. Most prominent within the CA fields are the labeled dendrites of pyramidal neurons. In many instances, apical dendrites can be traced into the adjacent stratum radiatum, where they impart a deep striated appearance to this region of the hippocampus. Robust GluR2/3 labeling is also observed within the pyramidal layer of Ammon's horn, with an order of staining intensity similar to that observed for GluRl. However, unlike GluRl labeling, which is localized predominantly along dendrites, GluR2/3 labeling is observed primarily in association with ceh bodies. Collectively, these data suggest that the molecular composition of the AMPA receptor complex may differ between the dendrite and soma of granule and pyramidal neurons within the hippocampal formation, so functionally we may predict that these two regions of the neuron would respond differently following glutamate receptor stimulation. © 1995 Wiley‐Liss, Inc.
Dopamine transporter immunoreactivity in rat brain
Authors: Freed Curt , Revay Randall , Vaughan Roxanne A. , Kriek Evelyn , Grant Steven , Uhl George R. , Kuhar Michael J. 
Published: January 2005

AbstractThe dopamine transporter (DAT) is a primary site for the action of cocaine in inducing euphoria. Its action is necessary for the selectivities of dopaminergic neurotoxins that provide the best current experimental models of Parkinson's disease. In the present report, rat ddpamine transporter‐like immunoreactivity (iDAT) was assessed by immunohistochemistry using newly developed polyclonal antisera raised against conjugated peptides corresponding to sequences found in the dopainine transporter's carboxy‐ and amino‐termini. Dense iDAT was observed in patterns consistent with neural processes and terminals in the striatum, nucleus accumbens, olfactory tubercle, nigrostriatal bundle, and lateral habenula. Perikarya in the substantia nigra pars compacts, were immunostained with moderate intensity using one of two immunohistochemical methods, while scattered ventral tegmental area perikarya were stained with somewhat less intensity. Immunoreactive neuronal processes with axonal and dendritic morphologies were stained in the substantia nigra and the paranigral and parabrachialis pigmentosus nuclei of the ventral tegmental area, while sparser processes were noted more medially in the ventral tegmental area. Neuronal processes were found in several laminae in the cingulate cortex, with notable fiber densities in the superficial aspects of lamina I and laminae II/III. The intensities of immunoreactivities in striatum and cerebral cortex were dramatically attenuated ipsilateral to nigrostriatal bundle 6‐hydroxydopamine lesions. Specificity of immunostaining was supported by agreement of the results using sera directed against two distinct DAT segments, studies with preimmune and preadsorbed sera and studies of the extracted protein. These antisera identify and reveal details of the distribution of DAT immunoreactivity in rat brain and display ivariations in levels of DAT expression of likely functional significance. © 1995 Wiley‐Liss, Inc.
The process of reinnervation in the dentate gyrus of adult rats: Gene expression by neurons during the period of lesion‐induced growth
Authors: Steward Oswald 
Published: January 2005

AbstractNeurons in the hippocampal dentate gyrus are extensively reinnervated following the destruction of their normal inputs from the ipsilateral entorhinal cortex (EC). The present study evaluates gene expression by dentate granule neurons and the neurons giving rise to the sprouting connections during the period of synapse growth.Adult male rats were prepared for in situ hybridization at 2, 4, 6, 8, 10, 12, 14, 20, and 30 days following unilateral EC lesions. Sections were hybridized using 35S‐labeled cRNA probes for mRNAs that encode proteins thought to be important for neuronal structure and/or synapse function, including (1) mRNAs that are normally present in dendrites‐the mRNAs for the high molecular weight microtubule‐associated protein 2 (MAP2) and the α‐subunit of calcium/calmodulin‐dependent protein kinase Il (CAMII kinase), (2) mRNAs that are upregulated in neurons that are regenerating their axons (Tα1 tubulin and F1/GAP43) and (3) mRNAs for proteins that are the principal constituents of neurofilaments and microtubules (the low molecular weight neurofilament protein NF68 and β‐tubulin).Although there were small changes in the levels of labeling for the mRNAs that are normally present in dendrites, there were no dramatic increases in the levels of any of the mRNAs either in dentate granule cells or in neurons giving rise to the reinnervating fibers at any postlesion interval. These results indicate that neurons in mature animals can substantially remodel their synaptic terminals and their dendrites in the absence of large‐scale changes in gene expression (at least as measured by steady‐state mRNA levels at various time points). © 1995 Wiley‐Liss, Inc.
Distribution in the central nervous system of Aplysia of afferent fibers arising from cell bodies located in the periphery
Authors: Xin Yuanpei , Weiss Klaudiusz R. , Kupfermann Irving 
Published: January 2005

AbstractThe present study used autoradiography to determine the location of the projections of presumptive peripheral afferent neurons into the central nervous system of Aplysia. Selected peripheral tissues (with an empliasis on structures involved in feeding behavior) were exposed to radioactive amino acids, and the distribution of macromolecules transported into the nervous system via afferent fibers was determined by autoradiography. Different regions of the body exhibited different patterns of projections, and within the neuropil of the cerebral ganglion, there was a loose topographical prganization of projections from the head. For some regions of the body, the projection was largely limited to the ganglion from which the nerve enters; for other regions, the projection was very widespread. In some cases (e.g., rhinophore to eye), there was evidence of projections from one peripheral structure to another. Experiments with all peripheral tissues that were studied resulted in extensive labeling of central ganglia, indicating that afferents with peripheral cell bodies may provide a major source of sensory input to the central nervous system and suggesting that many or all of the numerous ultrafine axons visualized via electron microscopy in the nerves of Aplysia may originate from first‐ or second‐order sensory afferents whose cell bodies are located in the periphery. © 1995 Wiley‐Liss, Inc.
Electroreceptor development in the electric fish Eigenmannia: A histological and ultrastructural study
Authors: Vischer Heinrich A. 
Published: January 2005

AbstractDevelopmental patterns of electroreceptors in the wealdy electric fish Eigenmannia were investigated by histological, histochemical, immunocytochemical, cell kinetic, ultrastructural, and computer‐assisted three‐dimensional reconstruction methods. The first cell of an electroreceptor primordium is embedded in the stratum germinativum of the epidermis. An unmyelinated, afferent nerve fiber ends near this cell below the basal lamina. Protrusions and vacuole‐like inclusions at the basal lamina above the nerve fiber ending suggest a mechanism of nervous induction. The receptor primordium cell subsequently divides into a single cell layer. Within 48 hours, a second apical cell layer forms from the first, and, thus, the primordium differentiates into an apical layer of presumptive receptor cells and a basal layer of presumptive supporting cells. While the two layers further differentiate into mature receptor and supporting cells, the afferent fiber penetrates the basal lamina, sprouts, and forms a synapse with each receptor cell. Transitory fibers also project along the receptor cells to the top of the developing electroreceptor but degenerate during development. Synapses are smaller in early developmental stages compared to older stages, and pre‐ and postsynaptic vesicles are more abundant and widely distributed in younger stages. Moreover, presynaptic ribbons are longer and are interconnected at their apical ends. Supporting cells continue to divide during further maturation and form new receptor cells. The number of receptor cells per tuberous organ increases during the first 4 days of electroreceptor development and plateaus when the fish are 9 days old. It declines again when organs begin to divide into clusters. © 1995 Wiley‐Liss, Inc.
Time‐course of neuropeptide changes in peri‐ischemic zone and amygdala following focal ischemia in rats
Authors: Cheung R. T. F. , Diab T. , Cechetto D. F. 
Published: January 2005

AbstractPreviously, using a middle cerebral artery occlusion model in Wistar rat, we showed autonomic disturbances similar to those seen clinically and observed striking neurochemical changes in cortical and subcortical sites at 5 days following stroke. The neurochemical changes may account for functional recovery and/or autonomic disturbances after focal ischemia. To understand the possible mechanisms and to facilitate future studies, it is necessary to define the time‐courses of these changes.Using immunohistochemical staining with the peroxidase‐antiperoxidase reaction, the changes in several neuropeptides over the peri‐ischemic region and the ipsilateral central and basolateral nucleus of the amygdala were investigated at different times after middle cerebral artery occlusion. In the experimental group, neuropeptide Y immunoreactivity appeared to increase by 6 hours in the peri‐ischemic region. Using image analysis to quantify the staining intensity, the change became statistically significant at 1 day, peaked around 3 days, and subsided at 10 days. There was a delayed increase in neuropeptide Y in the ipsilateral basolateral nucleus of the amygdala with a peak around 3 days. Immunoreactive staining for leucine‐enkephalin, dynorphin, and neurotensin demonstrated an increase that was localized to the ipsilateral central nucleus of the amygdala with a peak around 3 days and a return to baseline levels by 10 days.The results support a specific time‐course for each of the neuropeptides studied and indicate that a survival time of 3 days after focal ischemia is the critical period for examining the relationship between neuropeptide responses and neuronal or functional recovery. © 1995 Wiley‐Liss, Inc.
Human intermediate reticular zone: A cyto and chemoarchitectonic study
Authors: Huang Xu‐Feng , Paxinos George 
Published: January 2005

AbstractThe primary aim of this study was to provide a comprehensive account of the morpholo topography, and frequency of tyrosine hydroxylase‐ and substance P‐like (TH‐LI, SP‐LI) immunoreactive neurons of the human intermediate reticular zone (IRt), the putative autonomic zone of the medullary reticular formation. A further aim is to examine the IRt from a three‐dimensional perspective using computer reconstruction techniques and compare its relationship with other structures in the rest of the medullary reticular formation.Six adult human brains were obtained from individuals with no sign of cerebral disease and were perfusion fixed. Free‐floating transverse sections were immunostained with monoclonal antibodies against tyrosine hydroxylase and substance P by the avidin‐biotin‐peroxidase technique. The entire IRt displays TH‐LI cell bodies and fibers, and thus it is readily distinguishable from the neighbouring gigantocellular and parvicellular reticular nuclei. In contrast, SP‐LI cells are restricted to the external part of the IRt that is found in the open medulla, while SP‐LI fibers are more widely distributed. The IRt displays TH‐LI neurons which are fusiform, oval, and round in shape. The SP‐LI neurons of the IRt are primarily oval and fusiform. In preparations stained for Nissl substance, IRt cells were classified as pigmented and nonpigmented. A characteristic feature of the IRt is that its cells are larger (20 ± 4 μm) than those of the laterally adjoining parvicellular (12 ± 2 μm) and clearly smaller than those of the medially adjoining gigantocellular nuclei (33 ± 6 μm). The shape of the IRt is in keeping with the radial organization of the medulla with zones emanating from the fourth ventricle. Three‐dimensional computer recostructions of the cell plots show that (1) TH‐LI neurons extend through the entire IRt and densely packed in the rostral part of the ventrolateral IRt and (2) SP‐LI neurons are found only in the rostral half of the medulla oblongata. © 1995 Wiley‐Liss, Inc.
Immunocytochemical study of choline acetyltransferase in Drosophila melanogaster: An analysis of cis‐regulatory regions controlling expression in the brain of cDNA‐transformed flies
Authors: Yasuyama Kouji , Kitamoto Toshihiro , Salvaterra Paul M. 
Published: January 2005

AbstractWe have analyzed the cis‐regulatory regions in the 5′ flanking DNA of the Drosophila melanogaster choline acetyltransferase (ChAT; E.C. 2.3.1.6) gene by using germline transformants. These transformants are carrying wild‐type ChAT cDNA fused to different lengths of 5′ flanking sequence of the ChAT gene. Appropriate genetic crosses were used to introduce the transgene into animals with a presumptive null genetic background for endogenous ChAT. Expression of ChAT protein could thus be attributed exclusively to the transgene. Using a monoclonal antibody against Drosophila ChAT, we have investigated the spatial distribution of transgenic ChAT and compared it to the normal distribution of ChAT protein in wild‐type animals. The brains of 7.4 kb cDNA transformants showed a ChAT expression pattern similar to that of wild‐type anin in the first‐ and second‐order sensory neuropil but reduced expression in other highly ordered neuropil. Several lines that were transformed with 1.2 kb or 0.8 kb of 5′ flanking DNA demonstrated relatively normal expression in sensory neuropil. In addition, these lines also showed ectopic expression in higher order neuropil. In the optic lobe, the expression pattern directed by 7.4 kb of 5′ flanking DNA was very similar to that of wild‐type ChAT expression. In contrast, 1.2 kb or 0.8 kb transformants showed reduced levels of expression and a more limited pattern of distribution in the optic lobe. Our results suggest that the 5′ flanking DNA of the ChAT gene can be divided into several separable positive and negative regulatory regions, which define various subsets of cholinergic neurons in the nervous system. © 1995 Wiley‐Liss, Inc.