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

Fluoride-stimulated adenylate cyclase is demonstrated inisolated tumor cells of transplantable rat pituitary tumor MtT-F4 in vitro. The intracellular cyclic adenosine 3':5'-monophosphate is lowered in the cells incubated in the presence of synthetic somatostatin. Contrary to the findings reported for normal pituitary, however, the immunoreactive growth hormone release does not change when either somatostatin or phosphodiesterase inhibitors are present in the incubation medium. The presence of dibutyryl cyclic adenosine 3':5'-monophosphate (5 mM) in the incubation medium does not change the rate of growth hormone release by isolated tumor cells.
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PMID:Effect of somatostatin on growth hormone release by MtT-F4 rat pituitary tumor in vitro. 19 84

In a light microscopical study, we previously showed that more than 80% of somatostatin (SS) immunoreactive (-i) neurons in the hilus of the dorsal part of the rat dentate gyrus are lost 4 days after ischemia. In order to verify that the loss of SS immunostaining is due to an actual loss of the SS-i neurons and not merely a loss in expression of SS immunoreactivity, we have now performed an ultrastructural study of these neurons before and 40 h after 20 min of global cerebral ischaemia in adult rats. The normal SS-i neurons were multipolar and fusiform in shape. The SS-i product was associated with the endoplasmic reticulum and occasionally the Golgi apparatus. The cell nuclei had indentations of the nucleolemma and contained intranuclear rods. After ischaemia, many SS-i neurons in the dentate hilus showed increased electron density of both the cell nucleus and the cytoplasm. In addition the cytoplasm was heavily vacuolated with the SS-i associated with some of these vacuoles. Other SS-i neurons had, in addition to the vacuoles a more homogeneous, and abnormal electron lucent nucleus and cytoplasm. These ultrastructural changes correspond to previously reported irreversible, ischaemic cell changes of neurons. Based on this we conclude that the SS immunoreactivity in the dentate hilus of the dorsal hippocampus is lost after ischaemia because of neuronal necrosis. As a minor part of this study, we examined whether the ischaemia-susceptible SS-i neurons in dentate hilus had commissural axonal projections. This was done utilizing double fluorescence microscopy of retrograde axonal transport of the fluorescent dye, Fluoro-Gold, and the observation that vulnerable SS-i neurons display homogeneously dispersed immunostaining 40 h after ischaemia. Fluoro-Gold was injected unilaterally into the dorsal dentate gyrus 5 days prior to ischaemia. Then, 40 h after ischaemia, sections were stained for SS immunofluorescence, and examined, in the dentate hilus contralateral to the injection, for neuronal co-localization of both events. Cell counts revealed double-labelling of 13% of all neurons which displayed one of the events. This observation suggests that at least some of the ischaemia-susceptible SS-i neurons in dentate hilus do project commissurally. The pathophysiological significance of ischaemic loss of commissurally projecting SS-i neurons in dentate hilus remains to be determined.
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PMID:Ultrastructure of neurons containing somatostatin in the dentate hilus of the rat hippocampus after cerebral ischaemia, and a note on their commissural connections. 135 89

Many visceral afferent neurons contain peptides, which have been proposed as histochemical markers for nerve pathways of particular targets or as transmitter candidates. The former possibility was investigated in the present study. Primary afferent neurons which project to the urinary bladder, distal colon or penis of rats, and the colon of cats were labelled with retrogradely transported fluorescent dyes (Fast Blue, True Blue, or Fluoro Gold). One to six weeks after dye injection into the organs, lumbosacral dorsal root ganglia were removed, treated with colchicine, and processed for immunohistochemical identification of five peptides. Dye-labelled neurons were distributed in an organ-specific manner in the lower lumbosacral ganglia, where colon afferent neurons were almost exclusively found in S1 ganglia, penis neurons primarily in L6, and bladder neurons at both levels. Substance P- (SP), calcitonin gene-related peptide-(CGRP), vasoactive intestinal peptide- (VIP), enkephalin- (ENK), and somatostatin- (SOM) immunoreactivity (IR) were detected in neurons in all lumbosacral ganglia but only some of these peptides were present in a large percentage of labelled neurons. The numbers of peptide-containing neurons innervating each organ were CGRP greater than SP greater than VIP greater than ENK greater than SOM; however some differences were observed in the relative proportions of these neuronal populations between upper lumbar and lower lumbosacral ganglia and between different organs. The major difference seen at the upper lumbar level was amongst the SP-IR neurons, which were common (25-30%) amongst bladder and colon afferent neurons but absent in penis neurons.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Segmental distribution and peptide content of primary afferent neurons innervating the urogenital organs and colon of male rats. 161 47

Retrograde fiber tracing and in situ hybridization were used to determine expression of mRNAs for preprotachykinin A (ppTA), calcitonin gene related peptide (CGRP), preproenkephalin A (ENK), neuropeptide tyrosine (NPY) and somatostatin (SOM) as well as tyrosine hydroxylase (TH) in the petrosal ganglia primary sensory neurons which innervate carotid sinus baroreceptors and carotid body chemoreceptors. Perfusion of the carotid sinus with the retrogradely transported dye (Fluoro-Gold) labeled primary sensory neurons in petrosal ganglion. Numerous somata in the petrosal ganglion labeled with dye contained mRNAs for all the above peptides, except SOM. Moreover, TH mRNA was found in a substantial number of retrogradely labeled cells in the petrosal ganglion. This study provides information concerning which of the numerous peptides identified in sensory neurons of petrosal ganglion may be involved in modulation of the arterial baroreceptor and chemoreceptor reflexes.
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PMID:Expression of messenger RNAs for peptides and tyrosine hydroxylase in primary sensory neurons that innervate arterial baroreceptors and chemoreceptors. 168 84

The ventral aspect of the medulla oblongata of colchicine-treated rats was examined immunohistochemically using mouse monoclonal antibodies raised against somatostatin (SOM) and rabbit polyclonal antibodies to methionine enkephalin (ENK). Numerous perikarya showed positive immunostaining for both antisera. For the most part, the double-labelled cells were located (1) along the ventrolateral surface in a region that corresponds to nucleus paragigantocellularis, (2) in the region of nucleus gigantocellularis-nucleus raphe magnus and (3) in a discrete area just above the inferior olivary nucleus. In an attempt to determine the projection sites of the SOM/ENK somata, the retrogradely transported fluorescent dye Fluoro-Gold was injected into either the nucleus tractus solitarii (NTS) or the upper part of the thoracic spinal cord. SOM/ENK cells in all 3 regions were labelled by dye administered into the spinal cord whereas only those SOM/ENK cells located in nucleus paragigantocellularis were stained by dye microinjected into NTS. This is the first evidence of a SOM/ENK projection from the ventral medulla to either the spinal cord or NTS.
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PMID:Neurons of the ventral medulla oblongata that contain both somatostatin and enkephalin immunoreactivities project to nucleus tractus solitarii and spinal cord. 244 6

The origin of tachykinin- and calcitonin gene-related peptide-like immunoreactive (CGRP-LI) nerve fibres in the guinea pig carotid body and carotid sinus was determined by retrograde labelling of the carotid sinus nerve with Fluoro-gold and immunohistochemical double staining with fluorescein- and rhodamine-conjugated second antisera. Fluoro-gold-labelled perikarya with characteristic features of primary sensory neurones were numerous in the glossopharyngeal (petrosal) ganglion and occurred rarely in the closely attached superior vagal (jugular) ganglion. An efferent pathway from the brainstem could not be detected. Co-existence of tachykinin- and CGRP-LI was observed in 25-47% of labelled sensory neurones; less than 1% of Fluoro-gold-containing perikarya were exclusively stained by CGRP antiserum. Co-existence of tachykinin- and CGRP-LI was also demonstrated in nerve fibres of the carotid body and carotid sinus. Somatostatin-, cholecystokinin- and dynorphin-LI did not co-exist with tachykinin-LI in these fibres. Thus, tachykinin/CGRP-LI fibres in the carotid presso- and chemoreceptive areas exhibit a peptide pattern being generally characteristic for sensory fibres supplying great vessels in the guinea pig. In view of the present findings doubt is raised as to a primary involvement of these fibres in presso- or chemoreception, although a modulatory influence on these specific functions appears to be likely.
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PMID:Retrograde neuronal labelling and double-staining immunohistochemistry of tachykinin- and calcitonin gene-related peptide-immunoreactive pathways in the carotid sinus nerve of the guinea pig. 245 82

The CNS cell groups that innervate the sympathoadrenal preganglionic neurons of rats were identified by a transneuronal viral cell body labeling technique combined with neurotransmitter immunohistochemistry. Pseudorabies virus was injected into the adrenal gland. This resulted in retrograde viral infections of the ipsilateral sympathetic preganglionic neurons (T4-T13) and caused retrograde transneuronal cell body infections in 5 areas of the brain: the caudal raphe nuclei, ventromedial medulla, rostral ventrolateral medulla, A5 cell group, and paraventricular hypothalamic nucleus (PVH). In the spinal cord, the segmental distribution of virally infected neurons was the same as the retrograde cell body labeling observed following Fluoro-gold injections in the adrenal gland except there was almost a 300% increase in the number of cells labeled and a shift in cell group distribution. These results imply there are local interneurons that regulate the sympathoadrenal preganglionic neurons. In the medulla oblongata, serotonin (5-HT)-, substance P (SP)-, thyrotropin-releasing hormone-, Met-enkephalin-, and somatostatin-immunoreactive neurons of the raphe pallidus and raphe obscurus nuclei and the ventromedial medulla were infected. In the ventromedial and rostral ventrolateral medulla, immunoreactive phenylethanolamine-N-methyltransferase, SP, neuropeptide Y, somatostatin, and enkephalin neurons were infected. The A5 noradrenergic cells were labeled, as were some somatostatin-immunoreactive neurons in this area. In the were infected. The A5 noradrenergic cells were labeled, as were some somatostatin-immunoreactive neurons in this area. In the hypothalamus, tyrosine hydroxylase- and SP-immunoreactive neurons of the dorsal parvocellular PVH were infected. Only a few immunoreactive vasopressin, oxytocin, Met-enkephalin, neurotensin, and somatostatin PVH neurons were labeled.
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PMID:CNS cell groups regulating the sympathetic outflow to adrenal gland as revealed by transneuronal cell body labeling with pseudorabies virus. 254 65

In this study we examined the hypothesis that the intermediolateral cell column (IML) of the thoracic spinal cord, the nucleus from which preganglionic sympathetic neurons originate, provides an anatomical substrate through which selective regulation of sympathetic nervous system targets is accomplished. Preganglionic sympathetic neurons of rats were retrogradely labeled by the simultaneous exposure of the cervical sympathetic trunk (CST) and the adrenal medulla to Fluoro-Gold and True blue, contrasting fluorescent dyes. Retrograde labeling from these sites revealed 2 populations of sympathetic preganglionic neurons in IML whose distribution overlapped between segments T1 and T4. In regions where these 2 groups of retrogradely labeled neurons overlapped, sympathoadrenal preganglionic (SAP) neurons occupied the most lateral aspect of the nucleus. It was also determined whether individual retrogradely labeled neurons within these two groups sent axon collaterals to both the CST and adrenal medulla. Diamidino yellow, a fluorescent retrograde tracer dye that labels only nuclei, was substituted for Fluoro-Gold and used in combination with True blue to simultaneously label preganglionic sympathetic neurons projecting to either the CST or adrenal medulla. No double-labeled cell bodies were observed in spinal cords of rats treated in this manner. Thus it appeared that the efferent projections of these 2 cell populations in IML were target-specific. Immunohistochemical analysis of the relationship between nerve fibers in the IML and preganglionic sympathetic neurons was also undertaken in an attempt to classify further these 2 populations of sympathetic preganglionic neurons. Equal proportions of identified CST and SAP neurons appeared to be apposed by varicosities immunoreactive for either somatostatin or serotonin. On the other hand, when the comparison was based on whether oxytocin-immunoreactive varicosities appeared to appose these 2 populations of retrogradely labeled sympathetic neurons, a highly significant difference was revealed. That is, oxytocin-immunoreactive fibers and terminals appeared to avoid SAP neurons. Thus these data support the hypothesis that an anatomical substrate exists in spinal cord IML whereby selective regulation of sympathetic nervous system targets may be mediated. Moreover, the lack of oxytocin-immunoreactive varicosities apposing SAP neurons in IML suggests that if the paraventricular nucleus innervates SAP neurons in IML, it does so via a population of neurons that do not use oxytocin as a neurotransmitter.
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PMID:The intermediolateral cell column of the thoracic spinal cord is comprised of target-specific subnuclei: evidence from retrograde transport studies and immunohistochemistry. 289 66

The importance of nerve growth factor (NGF) for the development of sensory ganglia was investigated by injecting rat fetuses (16.50 days of gestation) with a single dose of anti-NGF antiserum. Four months later the treated animals showed a very large decrease in substance P- and somatostatin-like immunoreactivities in dorsal root ganglia and skin with a lesser decrease in trigeminal ganglia. Fluoride-resistant acid phosphatase, substance P-, and somatostatin-like immunoreactivities were greatly decreased in the dorsal horn of the spinal cord. No change in neurotensin- and [Met]enkephalin-like immunoreactivities was observed. The anti-NGF antiserum treatment produced a greater than 90% decrease in the number of unmyelinated dorsal root fibers and a 35% decrease in the total number of myelinated fibers. The loss in myelinated fibers was restricted to small-diameter fibers with no change in large-diameter fibers. No change in taste bud morphology was noted, thereby refuting the proposal that anti-NGF antiserum treatment may represent an animal model for familial dysautonomia. The present results indicate that NGF is a necessary requirement for the normal development of a significant population of prenatal rat dorsal root ganglion cells.
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PMID:Biochemical and anatomical effects of antibodies against nerve growth factor on developing rat sensory ganglia. 660 28

In this investigation we studied pancreastatin (PST) secretion from a human PST producing cell line (QGP-1N) in response to various secretagogues. Immunocytochemical study revealed the immunoreactivity of PST and somatostatin (SMT) in the same cells of a monolayer culture. Ki-ras DNA point mutation on codon 12 was found. Carbachol stimulated secretion of PST and SMT and intracellular Ca2+ mobilization in the range of 10(-6)-10(-4) M. The secretion and Ca2+ mobilization were inhibited by atropine, a muscarinic receptor antagonist. Phorbol ester and calcium ionophore (A23187) stimulated secretion of PST and SMT. The removal of extracellular calcium suppressed both secretions throughout stimulation with 10(-5) M carbachol. Fluoride, a well-known activator of guanine nucleotide binding (G) protein, stimulated intracellular Ca2+ mobilization and secretion of PST and SMT in a dose-dependent manner in the range of 5-40 mM. Also, 10(-5) M carbachol and 20 mM fluoride stimulated inositol 1,4,5-triphosphate production. However, cholecystokinin and gastrin-releasing peptide did not stimulate Ca2+ mobilization or secretion of the two peptides. These results suggest that secretion of PST and SMT from QGP-1N cells is regulated mainly by acetylcholine in a parallel fashion through muscarinic receptors coupled to the activation of polyphosphoinositide breakdown by a G-protein and that increases in intracellular Ca2+ and protein kinase C play an important role in stimulus-secretion coupling.
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PMID:Parallel secretion of pancreastatin and somatostatin from human pancreastatin producing cell line (QGP-1N). 809 76


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