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)

Transversal sections through the basal forebrain of 11 adult male rats were immunostained for glutamic acid decarboxylase (GAD), choline acetyltransferase (ChAT), somatostatin (SOM) and parvalbumin (PARV). Immunohistochemistry of ChAT, PARV, and SOM was combined with histochemistry of NADPH-diaphorase (NADPH-d) to obtain information on the colocalization of various neuroactive substances and this enzyme and to facilitate the recognition of morphological details of double-stained neurons. The distribution patterns of GAD- and PARV-immunoreactive cells were only in part congruent in basal forebrain nuclei in the rat. In the medial septal nucleus (MS) and the vertical limb of the diagonal band (vDB) PARV-immunopositive neurons were homogeneously scattered inside the nucleus, whereas the GAD-immunoreactive cells were much more numerous in the lateral part of this nuclear complex. In the horizontal limb of the diagonal band (hDB) and the nucleus preopticus magnocellularis (NPM), where GAD-immunoreactive cells occurred in high number, only very few cells contained PARV-immunoreaction product. In the substantia innominata-nucleus basalis Meynert complex (SI-NB) and in the ventral pallidum (VP) the neuropil was heavily stained with the GAD-immunoreaction product. The number of GAD-positive cells appeared low in the SI-NB, but much higher in the VP. In this nucleus GAD- and PARV-immunoreactive cells seem to be identical. PARV-positive neurons are very sparse in the SI-NB. Double-staining of PARV-immunoreactivity and NADPH-d was not registered. These nuclei were the only ones in which some cells with SOM-like immunoreactivity were observed. Among ChAT-positive neurons those double-stained with NADPH-d occurred in moderate number, but with obvious regional differences. In MS-vDB and the marginal zone of hDB the two neuron groups were intermingled, but only in the innermost part of the hDB ChAT-single-immunostained cells form aggregates, which were also typical of the zone in the SI-NB that surrounds and infiltrates the globus pallidus (GP). Double-labelled cells were more frequent in the lateral aspect of the NPM and SI-NB. Cells single-stained for NADPH-d were frequent in the MS-vDB along the border toward the lateral septal nuclei, but low in number in the NPM, VP and SI-NB. The functional aspects of the occurrence of GAD-immunoreactive cell aggregates in the lateral preoptic area (LP) and the lateral hypothalamic area (LH) were discussed with special regards to extrinsic GABAergic input in the dorsal SI-NB.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Morphology of neurons in the rat basal forebrain nuclei: comparison between NADPH-diaphorase histochemistry and immunohistochemistry of glutamic acid decarboxylase, choline acetyltransferase, somatostatin and parvalbumin. 168 12

The purpose of the present study was to determine whether neurochemicals normally found within neuron somata, fibers, and terminals of the hippocampal formation would also be present in transplanted hippocampal tissue that had developed in lesion cavities made in adult rat brains by aspiration of the hippocampus and overlying dorsolateral neocortex. Embryonic Day 15 or 16 rat brian tissue containing hippocampus with some medial pallial anlage was transplanted into the site of hippocampal aspiration lesions in adult male rats. One hundred ten to one hundred thirty-five days later the brains of these rats were sectioned and processed using the avidin-biotin-horseradish peroxidase immunocytochemical procedure to visualize choline acetyltransferase, met-enkephalin (MENK), neurotensin (NT), somatostatin, substance P, tyrosine hydroxylase (TH), or vasoactive intestinal polypeptide. Sections from two brains were stained using the thiocholine technique for visualization of acetylcholinesterase. All of these substances were found within cell bodies and/or fibers in the transplants. However, several abnormalities were noted. In addition to TH-immunoreactive fibers, TH-immunoreactive cell bodies were found in the transplants. Since TH is not expressed in mature hippocampal or cortical neurons this suggests that mechanisms for suppression of manufacture of this enzyme are lacking or inhibited in the transplants. Further, although all of the peptides were present either in fibers or in both cell bodies and fibers, the density of staining for NT and MENK was less than would be expected for normal hippocampus, and none of the cell bodies or fibers reacting for the peptides exhibited any apparent organization resembling that normally observed in hippocampus or cortex. However, some histological organization was present and the cholinergic markers were associated with this organization. These data suggest that some tropic and/or trophic factor such as nerve growth factor is present in the transplants to guide cholinergic innervation.
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PMID:Neurochemical anatomy of fetal hippocampus transplanted into large lesion cavities made in the adult rat brain. 170 34

The axonal transport blocker colchicine has been extensively used in immunohistochemical studies to induce accumulation of neuroactive compounds, especially neuropeptides, in neuronal somata and thus improve their visualization. To assess whether colchicine might, in addition, influence the synthesis of such compounds, we have now used in situ hybridization to examine the levels of mRNAs encoding for several neuropeptides (galanin [GAL], cholecystokinin [CCK], somatostatin [SOM], neuropeptide Y [NPY]) and neurotransmitter-synthesizing enzymes (choline acetyltransferase [ChAT], tyrosine hydroxylase [TH], amino acid decarboxylase [AADC], and glutamic acid decarboxylase [GAD]) after intraventricular administration of the drug. The results show that colchicine differentially modifies the levels of several mRNA species in different brain areas. Thus GAL mRNA levels increase in virtually all regions examined, including the basal forebrain, hypothalamus, dorsal raphe nucleus, locus coeruleus, and nucleus tractus solitarii. In addition, after colchicine treatment, GAL mRNA appears to be induced in the ipsilateral hemisphere in regions such as the cortex, hippocampus, striatum, lateral septum, and some nuclei of the thalamus as well as within white matter, where it cannot be detected in control animals. Although GAL mRNA in the vast majority of cases is neuronal, some findings indicate a possible glial localization. In parallel, colchicine depletes ChAT mRNA and increases GAD mRNA in the basal forebrain and striatum and decreases AADC mRNA in the dorsal raphe nucleus and locus coeruleus. In the latter nucleus, NPY and TH mRNA levels are increased by colchicine. In contrast, TH mRNA and also CCK mRNA levels decrease in the substantia nigra. In the cortex, hippocampus, and thalamus ipsilateral to colchicine injection CCK mRNA levels are markedly decreased, whereas SOM mRNA is decreased and NPY mRNA increased in the hippocampus but unchanged in the cortex. The results are discussed with reference to the possible artifacts that the use of colchicine might induce in immunohistochemical mapping studies and in relation to possible neurotoxic actions of colchicine, in some cases perhaps related to impaired retrograde transport of growth factor(s).
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PMID:Differential effects of intracerebroventricular colchicine administration on the expression of mRNAs for neuropeptides and neurotransmitter enzymes, with special emphasis on galanin: an in situ hybridization study. 170 58

NADPH diaphorase staining neurons, uniquely resistant to toxic insults and neurodegenerative disorders, have been colocalized with neurons in the brain and peripheral tissue containing nitric oxide synthase (EC 1.14.23.-), which generates nitric oxide (NO), a recently identified neuronal messenger molecule. In the corpus striatum and cerebral cortex, NO synthase immunoreactivity and NADPH diaphorase staining are colocalized in medium to large aspiny neurons. These same neurons colocalize with somatostatin and neuropeptide Y immunoreactivity. NO synthase immunoreactivity and NADPH diaphorase staining are colocalized in the pedunculopontine nucleus with choline acetyltransferase-containing cells and are also colocalized in amacrine cells of the inner nuclear layer and ganglion cells of the retina, myenteric plexus neurons of the intestine, and ganglion cells of the adrenal medulla. Transfection of human kidney cells with NO synthase cDNA elicits NADPH diaphorase staining. The ratio of NO synthase to NADPH diaphorase staining in the transfected cells is the same as in neurons, indicating that NO synthase fully accounts for observed NADPH staining. The identity of neuronal NO synthase and NADPH diaphorase suggests a role for NO in modulating neurotoxicity.
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PMID:Nitric oxide synthase and neuronal NADPH diaphorase are identical in brain and peripheral tissues. 171 81

The serous lingual glands of von Ebner secrete lingual lipase, an enzyme that begins fat digestion in the stomach. The objective of this study was to characterize the neuromodulators in the rat tongue and von Ebner glands using immunocytochemical techniques. Rat lingual tissues were fixed in formalin, embedded in paraffin and sectioned at 4 microns for light microscopic studies. Immunocytochemical localization of neuromodulators was performed with monospecific anti-rat neuromodulator IgG or control (preimmune) IgG as the primary antibody, using the peroxidase-antiperoxidase (PAP) technique. No staining was seen with control anti-rat IgG. Immunospecific staining for vasoactive intestinal peptide (VIP), tyrosine hydroxylase and choline acetyltransferase (CHAT) was observed in nerves in the tongue, and cells containing immunospecific staining for serotonin (5-hydroxytryptamine) were seen in the stroma between the lingual glands. Selected cells in the serous glands stained positively for the presence of substance P and somatostatin. Adrenergic, VIP-containing and cholinergic nerves appear to innervate the tongue and serous glands. Substance P and somatostatin were identified in cells of the lingual serous glands and may be additional local modulators regulating lingual lipase release.
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PMID:Neuromodulators of the lingual von Ebner gland: an immunocytochemical study. 171 11

It is well established that acetylcholine is a neurotransmitter at several distinct sites in the mammalian enteric nervous system. However, identification of the cholinergic neurons has not been possible due to an inability to selectively label enteric cholinergic neurons. In the present study an immunohistochemical method has been developed to localize choline acetyltransferase, the synthetic enzyme for acetylcholine, in order that cholinergic neurons can be visualized. The morphology, neurochemical coding and projections of cholinergic neurons in the guinea-pig small intestine were determined using double-labelling immunohistochemistry. These experiments have revealed that many myenteric neurons are cholinergic and that they can be distinguished by their specific combinations of immunoreactivity for neurochemicals such as calretinin, neurofilament protein triplet, substance P, enkephalin, somatostatin, 5-hydroxytryptamine, vasoactive intestinal peptide and calbindin. On the basis of their previously described projections, functional roles could be attributed to each of these populations. The identified cholinergic neurons are: motorneurons to the longitudinal muscle (choline acetyltransferase/calretinin); motorneurons to the circular muscle (choline acetyltransferase/neurofilament triplet protein/substance P, choline acetyltransferase/substance P and choline acetyltransferase alone); orally directed interneurons in the myenteric plexus (choline acetyltransferase/calretinin/enkephalin); anally directed interneurons in the myenteric plexus (choline acetyltransferase/somatostatin, choline acetyltransferase/5-hydroxytryptamine, choline acetyltransferase/vasoactive intestinal peptide); secretomotor neurons to the mucosa (choline acetyltransferase/somatostatin); and sensory neurons mediating myenteric reflexes (choline acetyltransferase/calbindin). This information provides a unique opportunity to identify functionally distinct populations of cholinergic neurons and will be of value in the interpretation of physiological and pharmacological studies of enteric neuronal circuitry.
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PMID:Immunohistochemical identification of cholinergic neurons in the myenteric plexus of guinea-pig small intestine. 172 93

The neurotoxic effects of prolonged exposure of rat striatum to quinolinic acid in vivo was evaluated through assays of neurochemical markers for major neuronal populations. Continuous intrastriatal quinolinic acid infusion for 14 days produced a dose-dependent depletion of striatal choline acetyltransferase (ChAT) activity, glutamic acid decarboxylase (GAD) activity, and somatostatin content. ChAT activity was significantly reduced by quinolinic acid at doses of 90, 270, and 540 nmol/day, while GAD activity and somatostatin content were decreased only at doses of 270 and 540 nmol/day. NADPH-diaphorase histochemistry revealed a loss of striatal NADPH-diaphorase neurons as a result of quinolinic acid infusion at a dose of 270 nmol/day. The neurotoxic lesion induced by prolonged quinolinic acid exposure in vivo can be used as a potential model for studying excitotoxic mechanisms in neurodegenerative disease.
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PMID:Prolonged infusion of quinolinic acid into rat striatum as an excitotoxic model of neurodegenerative disease. 182 44

The cholinergic differentiation factor (CDF) in heart cells is identical to leukemia inhibitory factor (LIF). Recombinant CDF/LIF was shown to alter dramatically neurotransmitter production as well as the levels of several neuropeptides in cultured rat sympathetic neurons. Here it is shown that these changes are likely to be caused by alterations in the mRNA for these proteins and peptides. Growth in 1 nM recombinant CDF/LIF induces mRNA for acetyl CoA: choline-O-acetyltransferase [EC 2.3.1.6; choline acetyltransferase (ChAT)], somatostatin (SOM), substance P, and vasoactive intestinal polypeptide while lowering mRNA levels of tyrosine hydroxylase (EC 1.14.16.2) and neuropeptide Y (NPY). In addition, the sizes of the mRNAs for ChAT, SOM, and NPY are larger after recombinant CDF/LIF treatment.
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PMID:Recombinant cholinergic differentiation factor (leukemia inhibitory factor) regulates sympathetic neuron phenotype by alterations in the size and amounts of neuropeptide mRNAs. 190 72

The question whether during the process of cholinergic degeneration somatostatin- and/or neuropeptide Y-containing neurons in rat hippocampus and cortex react to the withdrawal of cholinergic function was addressed. After bilateral intracerebroventricular injection of the cholinotoxin ethylcholine aziridinium (AF64A; 1 or 2 nmol/ventricle) in rats, the activity of choline acetyltransferase (ChAT) started to decline in the hippocampus within 24 h. The reduction of ChAT activity reached its maximum within 4 days (34 and 55% after 1 and 2 nmol of AF64A/ventricle, respectively) and persisted during the observation period of 14 days. In the parietal cortex, ChAT activity decreased by 23% 4 days after 2 nmol of AF64A/ventricle. The loss in ChAT activity was accompanied by a transient decline in the levels of somatostatin and a transient increase in the levels of neuropeptide Y in both brain areas. In the hippocampus, the reduction in somatostatin content was most pronounced after 2 days (by 22 and 33% after 1 and 2 nmol of AF64A/ventricle, respectively). Within 14 days, somatostatin levels returned to control values. Neuropeptide Y levels increased slightly by approximately 25% of control values in the hippocampus. The changes described were present in both the dorsal and ventral subfields of the hippocampus. Similar but less pronounced changes in levels of both neuropeptides were observed in the parietal cortex. The present data provide further evidence for a close neuronal interrelationship between cholinergic and somatostatin- and/or neuropeptide Y-containing neurons in rat hippocampus and parietal cortex.
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PMID:Cholinergic deficit induced by ethylcholine aziridinium (AF64A) transiently affects somatostatin and neuropeptide Y levels in rat brain. 196 35

Cell-cell contact appears to play a critical role in the expression of transmitter traits in developing neurons. We have previously shown that cell membrane contact induces the de novo appearance of choline acetyltransferase (CAT) in virtually pure cultures of dissociated sympathetic neurons. A membrane-associated CAT-inducing factor has been extracted and purified 5000-fold. This factor exerts differential effects on transmitter traits in cultured sympathetic neurons. After 3 days in vitro, neurons exposed to the factor contained 40-fold higher levels of the neuropeptide substance P than controls. Somatostatin exhibited a similar dramatic elevation. In contrast, the factor had no effect on leucine-enkephalin. Further, the specific activity of tyrosine hydroxylase was reduced to 5% of control activity in treated cultures. These effects occurred in the absence of any increases in cell number. Thus, it appears that cell contact via membrane-associated factors may exert differential effects on phenotypic expression.
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PMID:Regulation of neurotransmitter expression by a membrane-derived factor. 197 Jul 86


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