Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P20366 (substance P)
 21,176 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A juxtapapillary duodenal polyp (measuring 1.5 x 1.0 x 1.2 cm) was removed endoscopically in a 57-year-old man who had had recurrent intestinal bleedings. Histological examination revealed a typical duodenal gangliocytic paraganglioma with carcinoid and paraganglioma-like components, as well as neuroid portions with ganglion cells. Various neuroendocrine markers (neuron-specific enolase, chromogranin, protein-gene product 9.5) were demonstrated immunohistochemically. Tests for pancreatic polypeptide, substance P, enkephalin, cholecystokinin, glucagon and S-100 proteins, were all positive.
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PMID:[Juxtapapillary gangliocytic paraganglioma of the duodenum]. 270 35

An N-terminally directed antiserum to neurokinin B was raised in rabbits using an immunogen prepared by coupling the free-SH group of neurokinin B extended from its C-terminus by a cysteine residue (NKB-Cys) to an -NH2 group on human serum albumin using a heterobifunctional cross-linking reagent. In radioimmunoassay with 125I-Bolton-Hunter-labelled NKB-Cys as tracer, the antiserum showed no cross-reactivity with other tachykinins. An extract of a human pheochromocytoma, previously shown to contain peptides derived from preprotachykinin A, contained NKB-LI (13 pmol/g wet weight). The retention time of tumor neurokinin on reversed-phase HPLC was the same as that of synthetic neurokinin B. Peptides with the retention times of substance P, neurokinin A, neurokinin A (3-10)-peptide and neuropeptide K were also identified in the tumor extract. NKB-LI was not detected in extracts of a further nine pheochromocytomas or in five carcinoid tumors that expressed the preprotachykinin A gene.
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PMID:Neurokinin B in a human pheochromocytoma measured with a specific radioimmunoassay. 278 Apr 25

Antisera of defined regional specificity have been used to measure the concentration of substance P-like immunoreactivity (SP-LI) and neurokinin A-like immunoreactivity (NKA-LI) during a meal-induced flush in 10 patients with metastatic carcinoid tumours. Although all patients flushed, NKA-LI levels in five patients and SP-LI in six patients were not elevated relative to healthy subjects (NKA-LI, less than 3 pg/ml; SP-LI, less than 10 pg/ml) both in the fasted state and after food. In the patients with elevated basal plasma tachykinin levels, increases in NKA-LI and SP-LI after food were erratic and did not correspond to a defined digestive phase or the occurrence of the flush. Chromatographic analysis of plasma demonstrated the presence of neuropeptide K and neurokinin A, and the detection of COOH-terminal fragments of substance P is consistent with the higher levels of circulating SP-LI measured with a COOH-terminally directed antiserum compared with an NH2-terminally directed antiserum. Subcutaneous injection of the somatostatin analogue SMS 201-995 (50 micrograms) alleviated symptoms of flush in two of three patients but only partially suppressed NKA-LI and SP-LI concentrations. It is concluded that circulating tachykinins cannot be solely responsible for the meal-induced carcinoid flush.
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PMID:Circulating tachykinins (substance P, neurokinin A, neuropeptide K) and the carcinoid flush. 288 98

Tumour cells from a lymph-node metastasis of a midgut carcinoid tumour, immunoreactive for serotonin and substance P, were isolated and kept in culture for 2 months. The formation of large clusters or islets of tumour cells was paralleled by an increase in immunoreactive tachykinins (neuropeptide K and substance P) in the culture medium. The concentration of tachykinins declined subsequently despite good viability of the cells. Spontaneous release of serotonin into the culture medium was much greater than that of tachykinins, and remained stable throughout the study. These findings indicate different turnover rates and/or different storage sites for the peptides and the amine. In stimulation experiments, a dose-dependent release of serotonin, but not of tachykinins, was induced by a beta-adrenoceptor agonist (isoprenaline), while stimulation of alpha-adrenoceptors (noradrenaline) was not effective in releasing any of the substances. Pretreatment of the cultures with a beta-adrenoceptor antagonist (propranolol) or stimulations after calcium deprivation did not influence the isoprenaline-induced release of serotonin. These findings may indicate a modification of genuine beta-adrenoceptors during culture.
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PMID:Carcinoid tumour cells in long-term culture: release of serotonin but not of tachykinins on stimulation with adrenoceptor agonists. 290 16

An antiserum raised against neurokinin A has been used to demonstrate storage and release of neurokinin A-like immunoreactivity by carcinoid tumours. The antiserum showed reactivity towards members of the tachykinin family of polypeptides in the order: neurokinin A greater than eledoisin greater than neurokinin B greater than kassinin greater than substance P greater than physalaemin but the magnitude of the cross-reactivity with substance P and physalaemin was less than 1% of that of neurokinin A. A sensitive (IC50 238 fmol/ml; minimum detectable concentration, 9 fmol/ml) radioimmunoassay was set up using this antiserum. Extracts of metastatic tumour tissue from four patients with a primary carcinoid tumour in the midgut contained both neurokinin A-like immunoreactivity (NKA-LI) and substance P-like immunoreactivity (SP-LI). The concentrations (pmol/g wet weight) of NKA-LI and SP-LI in the tumours were: patient A 210, 201; patient B 2276, 6849; patient C 1198, 834 and patient D 424, 379. Analysis of the tumour extracts by reverse phase HPLC indicated that the NKA-LI was heterogeneous. Under two different conditions of chromatography, one component was eluted with the same retention time as neurokinin A. Two further components were more hydrophobic than neurokinin A but were not eluted with the retention time of neurokinin B. Analysis of these components by gel filtration indicated a molecular weight in the 3000-4000 range suggesting that they may be related to neuropeptide K, an N-terminally extended form of neurokinin A. NKA-LI and SP-LI were undetectable in the plasma of patients A and D but were elevated in patient B (NKA-LI 1005 +/- 114; SP-LI 345 +/- 85 fmol/ml) and patient C (NKA-LI 80 +/- 31; SP-LI 21 +/- 13 fmol/ml).
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PMID:Measurement and partial characterization of the multiple forms of neurokinin A-like immunoreactivity in carcinoid tumours. 300 57

A metastasis to the right liver lobe of an argyrophil/argentaffin midgut carcinoid tumour in a patient with the classical carcinoid syndrome was examined for the presence of tachykinins other than substance P, using a specific antiserum. The extract was initially purified using SepPak cartridges, and subsequently subjected to cation-exchange chromatography on SP Sephadex C-25 which separated the immunoreactive material into two main components (components I and II). Both were further purified by anion-exchange chromatography on DEAE-Sephadex A-25, and by reverse-phase fast protein liquid chromatography. Component II was identified as neurokinin A by its immunochemical and chromatographic properties and amino acid sequence analysis. Component I consisted of two molecular forms which were identified as neurokinin A(3-10) and neurokinin A(4-10) by amino acid sequence analysis. The tumour tissue contained only small amounts of the eledoisin-like peptide that has earlier been demonstrated in mammalian tissues. Although this component behaved like the nonmammalian peptide eledoisin on reverse-phase HPLC and on reverse-phase ion-pair chromatography, eledoisin-specific antiserum E2 indicated that eledoisin-like peptide is not identical to eledoisin. Neurokinin A in carcinoid tumours has an N-terminal heterogeneity; this multiplicity constitutes a further support for the hypothesis that carcinoid tumours produce a number of tachykinins which may be present in different relative amounts in individual patients and may contribute to the individual differences in symptomatology.
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PMID:Isolation and characterization of neurokinin A, neurokinin A(3-10) and neurokinin A(4-10) from a neutral water extract of a metastatic ileal carcinoid tumour. 303 49

The exact etiology of carcinoid flushing remains unknown, but the symptoms are probably mediated through release of one or several humoral substances. Flushing seen in fore-gut carcinoids (gastric carcinoids) has been ascribed to excessive histamine release, whereas flushing seen in mid-gut carcinoids (ileal carcinoids) tentatively has been ascribed to excessive release of serotonin, bradykinin, substance P, substance K or eledoisin. In this study plasma histamine was measured in 8 patients with mid-gut carcinoids and carcinoid syndrome using an enzymatic isotopic method in order to evaluate histamine as the vasoactive agent in patients with ileal carcinoid tumours and carcinoid syndrome. All patients had raised plasma histamine values. In patients with mid-gut carcinoids histamine may be one of the substances mediating flushing.
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PMID:Histamine in carcinoid syndrome. 318 38

An antiserum directed against the COOH-terminal region of neuropeptide K-(1-24)-peptide that shows only 0.5% reactivity with neuropeptide K has been used in radioimmunoassay to study the posttranslation processing of human beta-preprotachykinin. A primary midgut carcinoid tumor contained high concentration of substance P (2970 pmol/g), neurokinin A (3660 pmol/g) and neuropeptide K-(1-24)-peptide (3430 pmol/g) but only a very low concentration (less than 5 pmol/g) of intact neuropeptide K. Neuropeptide K-(1-24)-peptide was also detected in extracts of metastatic tumor tissue from four patients with midgut carcinoid tumors. The amino acid sequence of tumor neuropeptide K-(1-24)-peptide was identical to that predicted from the nucleotide sequence of a human beta-preprotachykinin cDNA. The fasting plasma concentration of neuropeptide K-(1-24)-peptide was elevated in a patient with the carcinoid syndrome (821 fmol/ml compared with less than 18 fmol/ml in healthy subjects) and rose approximately 2-fold after intravenous pentagastrin. The study has demonstrated that the Lys25-Arg26 bond in neuropeptide K (corresponding to Lys96-Arg97 in the precursor) is an important processing site in human beta-preprotachykinin.
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PMID:Neuropeptide K-(1-24)-peptide: storage and release by carcinoid tumors. 322 60

Tissue specimens from 5 patients with metastatic midgut carcinoid tumours were kept in organ culture for up to 6 months. The tumour cells were confined to the suspension in the form of condensed cell clusters and appeared to retain their endocrine characteristics. Radioimmunoassay for tachykinin immunoreactivity showed high concentrations in 4 out of 5 culture media. The concentrations were highest in the beginning of the experiment, but subsequently decreased. The 4 patients from which these tumours were taken had all elevated tachykinin concentrations in extracted plasma. The fifth culture medium had low tachykinin concentration, and the concentration in extracted plasma from this patient was within the normal range. Reversed-phase high-performance liquid chromatography of the culture media with elevated tachykinin concentrations revealed immunoreactive components with the characteristics of synthetic neuropeptide K, neurokinin A and eledoisin, components also found in plasma and tumour tissues of carcinoid patients. Our findings indicate that carcinoid tumour cells produce tachykinins. These peptides are biologically very active, resulting in flush and hypotension when infused intravenously into normals, and might contribute to the clinical symptoms of the carcinoid syndrome.
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PMID:Tachykinin production by carcinoid tumours in culture. 347 59

There is a recognised association between pernicious anaemia and the development of gastric carcinoma, endocrine cell hyperplasia, and carcinoid tumour. Multiple endoscopic biopsies from the body mucosa of seven patients with pernicious anaemia showed small intestinal metaplasia with varying degrees of inflammation, fibrosis, and expansion of the lamina propria. Using conventional silver and lead stains, endocrine cells were inconspicuous. Staining for the general neural and neuroendocrine markers NSE and PGP 9.5 revealed a proliferation of endocrine cells in the epithelium and isolated clumps of endocrine cells in the lamina propria. The clumps were composed of two cell types, either small or large. Some of these endocrine cells showed gastrin, 5HT, VIP and substance P immunoreactivity of varying intensity. Ultrastructurally nine morphologically distinct types of granules were found some of which correlated with the immunohistochemistry. Some separate islands were composed solely of endocrine cells while others had a definite neural component, suggesting that the former arise from 'budding off' of enteroendocrine cells and the latter originate from the neuroendocrine cells of the lamina propria plexus. Thus there may be a dual origin of carcinoid tumours. Carcinoid tumours associated with pernicious anaemia tend to be multifocal and are infrequent. Less than 50 such cases have hitherto been reported. Our findings of endocrine cells proliferations in seven cases of pernicious anaemia indicate that this may be an adaptive change that occurs frequently and provides the basis on which carcinoids, less frequently, develop.
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PMID:Pernicious anaemia and mucosal endocrine cell proliferation of the non-antral stomach. 352 38


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