bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cerebellin is a postsynaptic neuropeptide
Authors: Mugnaini Enrico , Dahl Anne‐Lise , Morgan James I. 
Published: January 2005

AbstractCerebellin is a hexadecapeptide that has been biochemically characterized and localized to cerebellar Purkinje cells and certain neurons of the dorsal cochlear nucleus (DCoN) of rat. Among rabbit antisera produced to synthetic cerebellins, one (C1) gave specific immunostaining of the Purkinje neuronal cell body, initial axon segment, and main stem dendrites, while another (R2) reacted with peripheral dendritic structures. This complementarity of staining was also present during cerebellar development. By electron microscopy, the immunoreaction product was localized to polyribosomal domains with antiserum C1 and to dendritic spines with antiserum R2, in both cerebellar cortex and DCoN. In the spine, the structure most strongly stained was the postsynaptic density, but some reaction product was adsorbed to the plasma membrane, the spine apparatus, and the granulofibrillar cytoplasmic component. Antiserum R2 also stained lysosome‐like bodies. We suggest that antiserum C1 recognizes cerebellin precursor(s) and antiserum R2 mature peptide(s) and perhaps degradation product. There is structural homology between cerebellin and residues 625–641 of the polyimmunoglobulin transporter. The functional implications of this homology and other possible roles of cerebellin are discussed.
Evidence for the co‐storage and co‐release of neuropeptide y and noradrenaline from large dense cored vesicles in sympathetic nerves of the bovine vas deferens
Authors: de Potter W. P. , Dillen L. , Annaert W. , Tombeur K. , Berghmans R. , Coen E. P. 
Published: January 2005

AbstractThe subcellular localization and the secretion of neuropeptide Y were studied in sympathetic nerve endings of bovine vas deferens.Immunostaining revealed a parallel distribution for neuropeptide Y and dopamine‐β‐hydroxylase immunoreactivity in the network of varicose nerve fibers in the smooth muscle layers of the vas deferens.Following differential centrifugation and sucrose density gradient centrifugation, neuropeptide Y was found to coincide with noradrenaline in the more dense region of the gradient, where the large dense cored vesicles are found.Superfusion experiments demonstrated the release of neuropeptide Y and noradrenaline upon electrical stimulation. Furthermore, the neuropeptide Y secretion was shown to be Ca2+‐dependent.We conclude that in the bovine vas deferens neuropeptide Y is only present in large dense cored vesicles of adrenergic neurons and that the peptide and noradrenaline are coreleased from these vesicles in a calcium dependent manner.
B‐endorphin disregulation in autistic and self‐injurious behavior: A neurodevelopmental hypothesis
Authors: Sandman Curt A. 
Published: January 2005

AbstractPeptides derived from pro‐opiomelanocortin (POMC) influence neurodevelopmental processes. Earlier studies indicated that MSH/ACTH compounds improved behavioral efficiency in retarded individuals. Recent studies have shown that opiate blockers reduce treatment‐resistant self‐injurious behavior (SIB), an autistic‐like, developmental disorder. Although the exact mechanisms are unknown, prenatal POMC disregulation, addiction to endogenous opiates and elevated pain threshold have been proposed to account for this behavior. In study one, four SIB patients were given 0, 25, 50 or 100 mg of naltrexone on separate weeks in a double blind, Latin square design. A specific dose dependent reduction in SIB was observed in three patients. In study two, plasma b‐endorphin was measured in 40 patients with SIB, a related behavior, stereotypy (ST) or controls. SIB and ST patients had higher levels of endorphin than controls. These data added new support for the role of b‐endorphin in a treatment‐resistant patient group.
Mammalian neuromuscular development accelerated with early but slowed with late gestational administration of ACTH Peptide
Authors: Rose Kenneth J. , Strand Fleur L. 
Published: January 2005

AbstractThe neuropeptide ACTH 4–10, a nonsteroidogenic fragment of adrenocorticotropic hormone, has two distinct and opposite effects on developing nerve and muscle. Muscle is positively influenced by ACTH during the first part of gestation (G days 3–12) before innervation occurs. Subsequent effects on innervation are largely depressive and exerted only during G13–21. Treatment during G3–12 increases twitch amplitude, rise time and speed of contraction of directly and indirectly stimulated extensor digitorum longus (EDL) muscle of two wk old rats. Treatment during G13–21 slows contractions of indirectly stimulated EDL, whereas treatment throughout gestation (G3–G21) shows little effect. Thus, ACTH first accelerates muscle development then modulates this development through neuronal depression.
Visualization of growth factor receptor sites in rat forebrain
Authors: Quirion Rémi , Araujo Dalia , Nair N. P. V. , Chabot Jean‐Guy 
Published: January 2005

AbstractIt is now known that various growth factors may also act in the central nervous system. Among them, it has recently been shown that epidermal growth factor (EGF) and insulin‐like growth factor I (IGF‐I) may possess trophic effects in the mammalian brain. We report here on the respective autoradiographic distribution of [125I]EGF and [125I]IGF‐I receptor binding sites in the rat brain, both during ontogeny and in adulthood. It appears that [125I]IGF‐I sites are more widely distributed both during ontogeny and in adulthood. These results reveal the plasticity of the expression of EGF and IGF‐I receptor sites in the mammalian brain. This could be relevant for the respective role of these two growth factors in the development and maintenance of neuronal function.
Recent developments in the use of synthetic oligonucleotides for in sity hybridization histochemistry
Authors: Lewis Michael E. , Krause Rudolph G. , Roberts‐Lewis Jill M. 
Published: January 2005

AbstractSynthetic oligonucleotides have been used with increasing frequency as probes for the detection and study of the regulation of specific mRNAs by in situ hybridization histochemistry. These probes can be easily obtained and used by the nonmolecular biologist, and they have been shown to be effective for the study of a wide range of mRNAs in neuronal and neuroendocrine tissues. Considerations in oligonucleotide probe design, synthesis, purification, and labeling are described in this article, and current procedures for tissue preparation and hybrization are discussed. In addition, control procedures and methods for the quantitation of in situ hybridization by image analysis are discussed. Finally, the combination of this technique with immunocytochemistry and retrograde tract‐tracing is reviewed. The coupling of quantitative in situ hybridization with other neuronal markers, e.g., of connectivity, provides an increasingly valuable technology for exploring the regulation of gene expression in a rich anatomical context.
Distribution of substance P‐like immunoreactive neurons in the human medulla oblongata: Co‐localization with monoamine‐synthesizing neurons
Authors: Halliday G. M. , Li Y. W. , Joh T. H. , Cotton R. G. H. , Howe P. R. C. , Geffen L. B. , Blessing W. W. 
Published: January 2005

AbstractThe raphe nuclei also contained SP‐like immunoreactivity (up to 30%) while few monoamine‐synthesizing neurons in the lateral and dorsomedial medulla contained SP‐like immunoreactivity approximately 5% of presumed serotonin‐, noradrenaline‐, and adrenthe adult human. The majority of SP‐like immunoreactive neurons were found in four main regions: the lateral medulla, the dorsomedial medulla, the spinal trigeminal nucleus, and the raphe nuclei. The morphology of immunoreactive cells varied according to the region in which they were found. In contrast to previous studies, we found large numbers (90,000) of SP‐like immunoreactive neurons throughout the adult human medulla oblongata. The distribution of these SP‐like immunoreactive neurons appears to be significantly different from those described in the rat and cat.These results were compared to the distributions of monoamine‐synthesizing and neuropeptide Y (NPY)‐like immunoreactive neurons in the human medulla previously reported (Halliday et al.: Neuroscience, in press, 1988a; J. Comp. Neurol., in press, 1988b). Colocalization studies revealed that many presumed serotonin‐synthesizing neurons in the raphe nuclei also contained SP‐like immunoreactivity (up to 30%) while few monoamine‐synthesizing neurons in the lateral and dorsomedial medulla contained SP‐like immunoreactivity (approximately 5% of presumed serotonin‐, noradrenaline‐, and adrenaline‐synthesizing neurons). The distributions of SP‐ and NPY‐like immunoreactive neurons were similar, although SP‐like immunoreactive neurons were concentrated in the lateral regions of the same structures. We have found that the distributions of monoaminesynthesizing, NPY‐, and SP‐like immunoreactive neurons significantly overlap, particularly in the lateral medulla of the adult human. There is a large increase in the number of these cells in this region compared to other species, emphasizing the neuroanatomical differences between humans and other species.
Evidence for release of copper in the brain: Depolarization‐induced release of newly taken‐up 67copper
Authors: Hartter Daryl E. , Barnea Ayalla 
Published: January 2005

AbstractThe potential importance of copper (Cu) in neurosecretion can be inferred from the demonstration that extracellular Cu modulates the secretory function of peptidergic neurons (in vitro studies) and from the presence of high Cu concentrations in nerve terminals and secretory vesicles, primarily within the soluble matrix of the latter. We have previously hypothesized that vesicular Cu is released from neurons undergoing exocytosis and that such extracellular Cu plays an important modulatory role in the central nervous system. To test this Cu release hypothesis, rat hypothalami were incubated under in vitro conditions for 1 or 2 hr with 20 nM radiolabeled Cu (67Cu), and then 67Cu release was stimulated by a depolarizing concentration (60 mM) of K+. K+ markedly (P < 0.001) stimulated 67Cu release in a Ca2+‐dependent manner (stimulated release was 95 fmol/10 min/mg protein after 1 hr 67Cu loading and 160 after 2 hr). These amounts of released 67Cu account for about 10% of the total 67Cu taken up by the tissue. These results indicate that part of the 67Cu taken up by hypothalamic explants is directed into an intracellular compartment from where it can be released by a Ca2+‐dependent mechanism, thus providing strong support to our hypothesis that release of copper is operative in situ in the brain.
Somatostatin and neuropeptide Y immunoreactivity in parkinson's disease dementia with alzheimer's changes
Authors: Flint Beal M. , Clevens Ross A. , Mazurek Michael F. 
Published: January 2005

AbstractSomatostatin‐like immunoreactivity (SLI) and neuropeptide Y‐like immunoreactivity (NPYLI) were measured in postmortem brain tissue from 12 control patients and 13 demented Parkinsonian patients who had Alzheimer‐type cortical pathology. Twenty‐two cortical regions were examined. Significant reductions in cortical SLI were found in 17 regions, while significant reductions in cortical NPYLI were found in nine regions. The reductions in SLI were typically 50–60%, while NPYLI reductions were 20–30%. These findings are similar to those in Alzheimer's disease (AD) and are consistent with a previous report of a dissociation between reductions in SLI and NPYLI in Parkinson's disease (PD) with dementia.
Peptide‐ and transmitter‐containing neurons in the mediobasal hypothalamus and their relation to GABAergic systems: Possible roles in control of prolactin and growth hormone secretion
Authors: Meister Björn , Hökfelt Tomas 
Published: January 2005

AbstractIndirect immunofluorescence histochemistry was used to study the relation among GABAergic, catecholaminergic, cholinergic, and peptidergic neurons in the rat mediobasal hypothalamus. By employing a direct double‐labelling procedure using sheep antiserum against glutamic acid decarboxylase (GAD), mouse monoclonal and rabbit antibodies to neurotensin (NT) and rabbit antisera to tyrosine hydroxylase (TH),choline acetyltransferase (ChAT), galanin (GAL), growth hormone‐releasing factor (GRF), or somatostatin (SOM), it was demonstrated that GAD‐positive fibers and terminals in the external part of the median eminence co‐contained immunoreactivity for TH, NT, GAL or GRF, but not for SOM. In the internal part of the median eminence‐infundibular stalk, GAD‐positive/NT‐, GAL‐, and GRF‐negative and GAD‐Positive/TH‐positive fiber plexa were shown. When a recently developed direct triple‐labelling procedure with biotinconjugated mouse secondary antibodies in conjunction with diethylaminocoumarin (DAMC)‐conjugated avidin was employed, presence of GAD/GAL/NT‐ as well as GAD/GRF/NT‐containing varicosities could be demonstrated close to hypophysial portal vessels. In colchicine‐pretreated animals, GAD was shown to coexist with TH, NT, or GAL in cell bodies in both the dorsomedial and ventrolateral domains of the arcuate nucleus, but with GRF only in the ventrolateral division. ChAT‐positive neurons in the ventrolateral region were also TH‐positive. In the ventrolateral arcuate nucleus, triple‐labelling followed by elution‐restaining showed GAD/NT/GAL/TH‐immunoreactivities in the same cells. Similarly, double‐labelling with two following elution‐restaining steps showed several NT/GAL/GRF/TH‐containing cell bodies in this part of the arcuate nucleus. GAD‐positive cells in the anterior hypothalamic periventricular area and fibers in the pituitary neurointermediate lobe were also TH‐positive.The results demonstrate complex patterns of storage of chemical messengers in neurons of the arcuate nucleus‐median eminence complex. Possible neuroendocrine interactions of these systems in the control of prolactin and growth hormone secretion are discussed.
Three‐dimensional structure of bidirectional, excitatory chemical synapses in the jellyfish Cyanea capillata
Authors: Anderson Peter A. V. , Grünert Ulrike 
Published: January 2005

AbstractNeurons in the ectoderm of the perirhopalial tissue of the jellyfish Cyanea capillata were exposed and fixed for electron microscopy under conditions designed to minimize exocytosis of synaptic vesicles. The structure of the bidirectional chemical synapses that connect neurons was examined and the three‐dimensional organization of these synapses was determined from reconstructions of serial sections. Synapses were characterized by the accumulation of a relatively few, large synaptic vesicles. These lie in a single layer against the terminal membrane of each terminal. The cytoplasmic side of the vesicles in any one terminal was covered by a single, large, perforated cisternal sheet. In addition, there were numerous smaller, bulbous cisternae that intermingled with the vesicles in the terminal. The structure of any one terminal was mirrored by that of the opposite terminal of the pair. The organization of these synapses is discussed from the viewpoint of cnidarian synapses in general.
Identification of 5‐hydroxytryptamine1D binding sites in human brain membranes
Authors: Peroutka Stephen J. , Switzer Julie A. , Hamik Anne 
Published: January 2005

AbstractHigh‐affinity, specific 3H‐5‐hydroxytryptamine (5‐HT) binding was analyzed in membrane homogenates of human frontal cortex, caudate, and globus pallidus. 5‐HT1A and 5‐HT1C binding sites were pharmacologically blocked using 100 nM 8‐hydroxy‐N,N‐dipropyl‐2‐aminotetralin (8‐OH‐DPAT) and 100 nM mesulergine, respectively. The majority of 5‐HT1 sites remained in each of the three brain regions under these conditions. The pattern of nucleotide interactions with these binding sites (GppNHp = GTP = GDP > GMP = adenine nucleotides) suggests a possible linkage to a G protein. RU 24969 competition studies confirmed the absence of 5‐HT1B binding sites in human cortex, caudate, and globus pallidus. Drug interactions with putative 5‐HT1D binding sites in bovine caudate membranes correlated significantly with their affinities for human membrane recognition sites labeled by 3H‐5‐HT in the presence of 100 nM 8‐OH‐DPAT + 100 nM mesulergine. We conclude that the majority of 3H‐5‐HT‐labeled recognition sites in human cortex, caudate, and globus pallidus represent 5‐HT1D binding sites.
Identification of L‐DOPA‐dopamine and L‐DOPA cell bodies in the rat mesencephalic dopaminergic cell systems
Authors: Mons Nicole , Tison Francois , Geffard Michel 
Published: January 2005

AbstractAn immunocytochemical technique for simultaneously visualizing two different antigens, dihydroxyphenylalanine (L‐DOPA) and dopamine (DA), has been used to investigate the presence of cell bodies containing both compounds L‐DOPA and DA and those having only L‐DOPA in rat mesencephalon areas. The brain slices were processed with a double peroxidase‐antiperoxidase method using simultaneously an incubation of a rabbit anti‐L‐DOPA serum and a monoclonal anti‐DA antibody raised in mouse. Both antigens were revealed by the peroxidase reaction but with different chromogens that are easily distinguishable. In this staining procedure, the first antigen, conjugated DA was stained using the 3,3′‐diaminobenzidine (DAB)‐Nickel complex; while the second antigen, conjugated L‐DOPA, was localized using DAB. The yellow‐brown color due to DAB was masked by that of DAB‐nickel. The possible existence of both single and double labelings could be worked. We have found many L‐DOPA‐positive/DA‐positive and a few L‐DOPA‐positive/DA‐negative cell bodies in dopaminergic regions in the rat midbrain: substantia nigra, ventral tegmental area, and raphe nuclei. In the locus coeruleus, we noted only L‐DOPA‐positive/DA‐positive cell bodies. These results confirm those previously described for rat and cat hypothalamus, where both immunoreactive‐cell body types have been detected: L‐DOPA positive/DA positive and L‐DOPA positive/DA negative. The existence of neuronal cells containing only L‐DOPA is a new neuroanatomic finding, accounting better for the heterogeneity of dopamine systems with respect to physiologic, pharmacologic, and molecular data.
Characterization of [3H]AF‐DX 116 binding sites in the rat brain: Evidence for heterogeneity of muscarinic‐M2 receptor sites
Authors: Araujo Dalia M. , Lapchak Paul A. , Regenold William , Quirion Remi 
Published: January 2005

AbstractThis study shows that [3H]AF‐DX 116 binds specifically, saturably, and with high affinity to putative muscarinic‐M2 receptor sites in the rat brain. In homogenates of the hippocampus, cerebral cortex, striatum, thalamus, and cerebellum, [3H]AF‐DX 116 appears to bind two subpopulations of muscarinic sites: one class of higher affinity sites (Kd < 4.0 nM) and one class of lower affinity sites (Kd > 50 nM, except in the cerebellum). The apparent maximal capacities (Bmax) of [3H]AF‐DX 116 sites in forebrain tissues ranged between 34 and 69 fmol/mg protein for the higher affinity site, and between 197 and 451 fmol/mg protein for the lower affinity site. In cerebellar homogenates, the maximal capacity of [3H]AF‐DX 116 binding sites was 10.4 ± 0.4 (Kd = 1.9 ± 0.2 nM) and 39.1 ± 2.6 (Kd = 26 ± 7 nM) fmol/mg protein for the higher and the lower affinity site, respectively. Determination of the Kd for the higher and lower affinity [3H]AF‐DX 116 sites from association and dissociation constants yielded similar values to those obtained from the saturation data. The ligand selectivity pattern reveals that AF‐DX 116 is more potent than (–)QNB > atropine > methoctramine > 4‐DAMP > gallamine > NMS > carbamylcholine > oxotremorine > pirenzepine > > nicotine in competing for the higher affinity [3H]AF‐DX 116 sites. With few exceptions, the pattern was similar for the lower affinity sites. For example, (–)QNB was more potent than AF‐DX 116 and pirenzepine was more potent than either oxotremorine or 4‐DAMP at the lower affinity [3H]AF‐DX 116 sites. In addition, pirenzepine was modestly more potent at the lower compared to the higher affinity sites. Neither the higher nor the lower affinity [3H]AF‐DX 116 sites were sensitive to the effects of Gpp(NH)p or N‐ethylmaleimide. In addition, the carbamylcholine‐induced inhibition of [3H]AF‐DX 116 binding to the higher and the lower affinity sites was altered by Gpp(NH)p and NEM, to a similar extent. However, Gpp(NH)p decreased the affinity of carbamylcholine (i.e., increased the IC50), whereas N‐ethylmaleimide had the opposite effect. Furthermore, N‐ethylmaleimide also appeared to steepen the curve for the carbamylcholine‐induced inhibition of [3H]AF‐DX 116 binding, as evidenced by the increased nH. Thus it appears that [3H]AF‐DX 116 binds to two subsets of muscarinic‐M2 receptors in the rat brain, which can be differentiated by their affinity for certain agonists and antagonists.
Region‐Specific loss of α1‐adrenergic receptors in rat brain with aging: A quantitative autoradiographic study
Authors: Burnett Donald M. , Zahniser Nancy R. 
Published: January 2005

AbstractThe effects of aging on the density and affinity of α1‐adrenergic receptors (α1‐ARs) were studied in several circumscribed areas of the Fischer 344 male rat brain. Computer‐assisted quantitative autoradiography was used to analyze saturation binding isotherms of [125I]BE‐2254, a selective α1‐AR antagonist. Significant decreases in receptor density of 15 and 29% were observed in the thalamus at 16–18 and 24–28 months of age, respectively, when compared to 3–4 month‐old controls. Progressive declines in receptor density of 24 and 44% were also found in the olfactory tubercle. In the cerebral cortex, a significant 26% loss in receptors occured only in the oldest age group. No changes were found in any of the other brain areas investigated, including the cerebellum, brainstem, caudate‐putamen, and several subregional areas of the hippocampal formation. Kd values ranged from 12 ± 1.8 pM in the brainstem to 23 ± 1.6 pM in the thalamus and were not affected by aging in any area examined. It is concluded that the density of α1‐ARs in the Fischer 344 rat brain is diminished with aging in a region‐specific manner and that loss of these receptors may account for age‐related functional deficits only in a few brain areas.
Acute effects of alprazolam and adinazolam on the concentrations of corticotropin‐releasing factor in the rat brain
Authors: Owens Michael J. , Bissette Garth , Nemeroff Charles B. 
Published: January 2005

AbstractCorticotropin‐releasing factor (CRF) is the major physiological regulator of the hypothalamic‐pituitary‐adrenal (HPA) axis. However, considerable evidence indicates that CRF may be responsible for integrating not only the endocrine, but the autonomic and behavioral responses of an organism to stress as well. In addition, clinical studies indicate that CRF of both hypothalamic and extrahypothalamic origin may be hypersecreted in major depression as well as other psychiatric disorders.These findings, taken together, led to the hypothesis that the efficacy of antidepressant and/or anxiolytic drugs may be related to their actions on CRF‐containing neural pathways in the central nervous system (CNS). Therefore, alterations of CRF concentrations in 18 rat brain regions were studied after acute administration of a tricyclic antidepressant (imipramine) or one of two triazolobenzodiazepines (alprazolam or adinazolam) that possess anxiolytic properties typical of benzodiazepines, as well as purported antidepressant activity unique to these compounds.Treatment with alprazolam or adinazolam increased hypothalamic CRF concentrations, which was associated with lower plasma ACTH concentrations. In contrast, the concentration of CRF was markedly reduced in the locus coeruleus, amygdala, and several cortical regions by either triazalobenzodiazepine. Acute treatment with imipramine was without effect on CRF concentrations in any brain region studied.Of particular interest is the finding that the two triazolobenzodiazepines exert effects on CRF concentrations in the locus coeruleus and hypothalamus that are opposite to CRF changes seen after stress.