Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P61278 (somatostatin)
 22,083 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The morphology and distribution of perikarya positive for choline acetyltransferase, somatostatin, calcium binding protein (calbindin D28K) and nicotinamide adenine dinucleotide phosphate diaphorase were surveyed in the human striatum. Choline acetyltransferase and somatostatin antibodies labeled separate populations of large striatal interneurons. Somatostatin immunoreactivity and nicotinamide adenine dinucleotide phosphate diaphorase (nitric oxide synthase) activity were completely co-localized. Calbindin antibody identified two distinct groups of striatal neurons: (1) numerous medium-sized, lightly stained neurons, probably analogous to striatopallidal projection neurons in the rat, and (2) much less numerous, large, darkly stained neurons. Half of the latter group, but none of the former, were also nicotinamide adenine dinucleotide phosphate diaphorase-positive. Somatostatin-positive and medium-sized, calbindin-positive neurons were more numerous in the caudate nucleus than in the putamen or ventral striatum. By contrast, large calbindin-immunoreactive neurons were more frequently encountered in the putamen. Choline acetyltransferase-positive neurons were evenly distributed across striatal components. In aged control subjects, the size of large, darkly stained calbindin-positive neurons was reduced relative to young subjects. Aging had no effect on somatostatin-, medium-sized calbindin-, or choline acetyltransferase-positive neurons. However, in histologically confirmed cases of Alzheimer's disease, there was a selective, 75% loss of choline acetyltransferase-immunoreactive perikarya from the ventral striatum, but not from the dorsal striatum, compared to aged controls. Furthermore, the remaining cholinergic neurons in the ventral striatum of Alzheimer's disease cases were significantly smaller than similar neurons in controls. These results indicate that various striatal components which have been shown to differ in their anatomical connectivity and functional specialization, also differ in their neurochemical signatures. The specific and marked loss of choline acetyltransferase-positive neurons from the ventral striatum in Alzheimer's disease is consistent with the characteristic cholinergic and 'limbic' pathology in this disease.
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PMID:Human striatum: chemoarchitecture of the caudate nucleus, putamen and ventral striatum in health and Alzheimer's disease. 752 83

Cholinergic markers, neuropeptides, and amines and their metabolites were sampled from identical specimens across 10 neocortical regions in a large sample of Alzheimer's disease (AD) cases and controls. Levels of choline acetyltransferase, acetylcholinesterase, somatostatin, corticotropin-releasing factor, serotonin, and 5-hydroxyindoleacetic acid were significantly reduced in AD versus controls. After data reduction, the most descriptive neurochemical indices were used to examine the relationship of neurochemical measures and dementia severity within the AD sample, controlling for age effects. Dementia severity ratings were based on antemortem assessments (46.9% of AD sample) and postmortem chart review (53.1% of the AD sample). Choline acetyltransferase activity was highly correlated with clinical dementia ratings across the neocortex of the AD cases. Somatostatin and corticotropin-releasing factor levels were correlated with dementia severity only when control cases were included in the analyses. None of the amines, their metabolites, or the neuropeptides quantified related significantly to dementia severity in the AD cohort. These data (a) confirm the strong association of cholinergic deficits with functional impairment in AD and show that this association is independent of age and (b) suggest that of all the neurochemical species quantified, the cholinergic indices may be unique in their association with dementia severity.
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PMID:Neurochemical correlates of dementia severity in Alzheimer's disease: relative importance of the cholinergic deficits. 783 69

Impairment of the basal forebrain cholinergic system is an important change in the brains of Alzheimer's disease patients. Various neurotoxins have been used to achieve this in animal models. In this study the effects of chemical lesions by ibotenic acid (IBO), a glutamate analogue and by 192 IgG-saporin, a highly specific immunotoxin against cholinergic neurons, were investigated. The toxins were delivered stereotaxically into the brains of young Sprague-Dawley rats which were later sacrificed by decapitation. Choline acetyltransferase (ChAT) activity was measured by radioenzymatic assay and substance P (SP), neuropeptide Y (NPY) and somatostatin (SOM) levels by radioimmunoassay. Decreased ChAT and SOM levels were observed in the cortex and the hippocampus in both experiments. Cortical SP levels were increased after IBO lesions but were unaffected after 192 IgG-saporin lesions. NPY levels remained unchanged in both experiments. The results indicate that there were specific changes in neuropeptide contents in the cortex and hippocampus in response to cholinergic damage in the rat brain.
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PMID:Cholinergic lesions of the rat brain by ibotenic acid and 192 IgG-saporin: effects on somatostatin, substance P and neuropeptide Y levels in the cerebral cortex and the hippocampus. 975 27

The study was aimed at the immunohistochemical characterization of myenteric Stach type V neurons of the pig ileum that were not included in the widely used Dogiel classification. So far, this conspicuous population has been defined morphologically on the basis of silver-impregnated specimens only. By using neurofilament immunohistochemistry, type V neurons that occur singly or in aggregates could be identified unequivocally and could be distinguished from other smoothly contoured myenteric neurons, i.e., type II and type IV. Double-labeling immunohistochemistry revealed a number of potentially neuroactive substances or their synthesizing enzymes to be present in type V neurons. Choline acetyltransferase immunoreactivity (-ir) was found in all type V neurons, whereas neuronal nitric oxide synthase was detected in none. Leu-enkephalin-ir was found within 92.3%, somatostatin (SOM)-ir within 91.1%, calcitonin gene-related peptide (CGRP)-ir within 80.6% and met-enkephalin-ir within 74.7% of type V neurons. Triple-labeling immunohistochemistry was applied to address the question of a specific chemical coding for myenteric type V neurons. In contrast to other combinations of neuroactive substances/enzymes that were found in both type V and other, nontype V neurons, SOM/CGRP-ir was the only combination observed exclusively within type V neurons. Both substances were colocalized in 79.3% of type V neurons. This colocalization discriminates four-fifths of the type V neurons chemically from both type II neurons (CGRP positive, SOM negative) and type IV neurons (CGRP negative, SOM positive), which both share, at first glance, a similar morphology with type V neurons. These results further support the concept of a close correlation between morphologically defined neuronal type and chemical coding and, it is likely, also function in the enteric nervous system of larger mammals.
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PMID:Correlated morphological and chemical phenotyping in myenteric type V neurons of porcine ileum. 1235 27

The aim of our study was to evaluate the involvement of essential pro- and antisecretory neurotransmitters in regulation of secretion in porcine proximal colon. Choline acetyltransferase (ChAT), nitric oxide synthase (NOS), vasoactive intestinal peptide (VIP), substance P (SP), somatostatin (SOM) and neuropeptide Y (NPY) were located immunohistochemically in the epithelium and subepithelial layer. Modulation of epithelial secretion was studied in Ussing chambers. Application of carbachol (CA), sodium nitroprussid (SNP), VIP and SP but not of NPY or SOM resulted in a chloride dependent increase in short circuit current (I(sc) ). I(sc) increase induced by CA, VIP or SNP was not altered by preincubation with tetrodotoxin or indomethacin. In contrast, SP-induced I(sc) increase was diminished by preincubation with tetrodotoxin, indomethacin, L-nitro-arginin-methyl-ester, and atropine but not hexamethonium. Simultaneous application of CA and VIP, or CA and SNP increased the I(sc) stronger as expected. Applying SP/CA led to a smaller increase in I(sc) as calculated. It is concluded that mainly prosecretory neurotransmitters are involved in regulation of colonic secretion. Cross-potentiations of acetylcholine and nitric oxide and acetylcholine and VIP suggest activation of different intracellular cascades. Similar intracellular pathways may be stimulated by acetylcholine and SP, thus preventing an additive effect of the transmitters.
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PMID:Modulation of electrogenic transport processes in the porcine proximal colon by enteric neurotransmitters. 2162 32


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