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)

Both salmon calcitonin (SCT) and substance P decreased ileal Na absorption, changed Cl transport from net absorption to net secretion and elevated the short circuit current when added in vitro at concentrations of 10 microng per ml to solutions bathing the serosal surface of rat ileum which had been stripped of its serosal muscle coat. The effects of substance P were of greater magnitude but shorter duration than SCT. Both peptides also increased the bidirectional fluxes of Ca but did not alter net Ca movement. The changes in Na and Cl fluxes and short circuit current are identifical to those which occur when cellular levels of cyclic AMP increased. However, incubation of ileal mucosa with SCT or substance P did not cause a detectable change in cellular levels of cyclic AMP or cyclic GMP. Both the mechanism of action and the possible physiological functions of SCT and substance P in the regulation of electrolyte transport require further investigation. The results with SCT appear to confirm prior suggestions that calcitonin may act directly to produce secretory diarrhea under pathophysiological conditions.
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PMID:Effects of calcitonin and substance P on the transport of Ca, Na and Cl across rat ileum in vitro. 19 61

1. Neurokinin A (NKA) is a mammalian tachykinin distributed principally in the nervous system, including the myenteric innervation of the gut. 2. NKA may be involved in neurogenic inflammation and as a modulatory factor in the diarrhoea associated with mucosal inflammation of inflammatory bowel disease (ulcerative colitis). 3. We evaluated the effect of NKA on the short-circuit current ISC, assumed to reflect electrogenic chloride secretion, across muscle-stripped rat colonic mucosa mounted in Ussing chambers. 4. Serosal addition of NKA produced a concentration-dependent (0.1-100 nM) increase in ISC with an EC50 (half-maximal effective concentration) value of 7.5 nM. The maximum (mean +/- S.E.M.) increase in ISC (microA/cm2) for NKA was 111 +/- 10. 5. Tetrodotoxin (0.5 microM) and bumetanide (10 microM), but not atropine (1.0 microM), hexamethonium (100 microM) or pyrilamine (10 microM), significantly inhibited NKA-induced increases in ISC. 6. The response to NKA was attenuated by 45 min pre-treatment with antisera raised against vasoactive intestinal polypeptide (VIP). Moreover, prior desensitization to VIP attenuated the effect of NKA. 7. These studies suggest that NKA increases ISC in rat colon, in part, through a non-cholinergic neural mechanism involving VIP.
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PMID:Neurokinin A increases short-circuit current across rat colonic mucosa: a role for vasoactive intestinal polypeptide. 165 54

By means of radioimmunoassay, the mucosal substance P (SP) and vasoactive intestinal polypeptide (VIP) concentration in distal ileum, transverse colon and sigmoid colon in 30 patients of chronic diarrhea with splenic weakness was determined and compared with that in 28 patients of chronic diarrhea without splenic weakness and in 15 controls without chronic diarrhea. In patients of chronic diarrhea with splenic weakness, the SP contents in the mucosa of distal ileum (120.95 +/- 90.70 pg/mg wet weight) was significantly increased compared with that in controls without diarrhea (47.86 +/- 35.49 pg/mg wet weight) and in chronic diarrhea without splenic weakness (52.50 +/- 42.49 pg/mg wet weight), P less than 0.01 and 0.01 less than P less than 0.05 respectively. The VIP contents of sigmoid mucosa in patients of chronic diarrhea with splenic weakness (510.63 +/- 265.22 pg/mg wet weight) was markedly increased in comparison of that in controls without chronic diarrhea (308.67 +/- 204.49 pg/mg wet weight), 0.01 less than P less than 0.05, and was not significantly augmented compared with that in chronic diarrhea without splenic weakness (398.97 +/- 240.80 pg/mg wet weight), but the tendency of increase was present. Our results suggested that the increased SP and VIP in patients of chronic diarrhea with splenic weakness might be closely related to the symptom of chronic diarrhea. According to the general function of VIP, the authors predicted that VIP might play a more important role in the pathogenetic action of chronic diarrhea with splenic weakness.
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PMID:[A preliminary study on substance P and vasoactive intestinal polypeptide contents in intestinal mucosa of chronic diarrhea with splenic weakness]. 171 57

We have previously shown that Entamoeba histolytica lysates contain the neurohormones serotonin, neurotensin, immunoreactive substance P, and probably acetylcholine, and that amebic lysates inhibit sodium and chloride absorption and stimulate chloride secretion in the rat descending colon as measured by the Ussing chamber-voltage clamp technique. We now demonstrate that these transport effects have both calcium-dependent and calcium-independent components. In addition, arachidonic acid metabolites of the cyclooxygenase pathway are probably involved in the Entamoeba histolytica-induced changes in colonic transport that are not dependent on Ca++ entry. Prostaglandin E2 (10(-5) M), indomethacin (10(-6) M), piroxicam (5 x 10(-5) M), and mepacrine (10(-4) M) partially inhibited the amebic lysate effect on active transport in the rat descending colon. In addition, verapamil (10(-4) M) partially inhibited the effect of amebic lysates. The effect of verapamil was additive with that of indomethacin, totally blocking the effect of amebic lysate on short-circuit current. However, amebic lysates do not contain prostaglandin E2 as measured by sensitive radioimmunoassay. Amebic lysates stimulated prostaglandin E2 release from rat colonic mucosal strips. Amebic lysate significantly increased colonic cyclic adenosine monophosphate content. Piroxicam inhibited the lysate-induced increase in colonic cyclic adenosine monophosphate content. These results indicate that although amebic lysate does not contain prostaglandin E2, it caused arachidonic acid metabolites to be produced by the cyclooxygenase pathway, and these are probably involved in the Entamoeba histolytica-induced changes in colonic transport. Neurohormones in Entamoeba histolytica may act directly on colonic tissue to stimulate intestinal secretion, probably via a Ca+(+)-dependent mechanism that is blockable by verapamil, or indirectly via stimulation of prostaglandin E2 generation and release from the rat colon via a cyclic adenosine monophosphate-dependent mechanism. These effects appear separate. The cyclic adenosine monophosphate-dependent secretion is the predominant mechanism in this model of colonic amebic diarrhea.
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PMID:Role of prostaglandins and calcium in the effects of Entamoeba histolytica on colonic electrolyte transport. 222 9

The carcinoid syndrome can arise when effluent blood from carcinoid tumor tissue gains access to the systemic, as opposed to the portal, venous system. Features include facial flushing, diarrhea, wheezing, right-sided cardiac lesions, and retroperitoneal fibrosis. Attacks of flushing, diarrhea, and wheezing can be provoked by bolus injections of adrenaline, noradrenaline, or pentagastrin. While serotonin usually predominates, carcinoid tumors can also secrete, in varying proportions, 5-hydroxytryptophan, kallikrein, kinins, substance P and other neuropeptides, prostaglandins, catecholamines, and histamine. Of these, serotonin, kinins, histamine, and substance P are possible mediators of flushes; serotonin and substance P of hyperperistalsis; and serotonin, kinins, or histamine of bronchial constriction. Despite the gross excess of circulating serotonin, nearly all is platelet bound and therefore inactive. Very little is free in plasma. Demonstration of a contribution of serotonin to carcinoid attacks requires assay of free plasma serotonin; measurements of whole blood or serum serotonin are of little value. Some, but not all, provoked flushes have been shown to be accompanied by a rise in free plasma serotonin or substance P; an increase in circulating kinins has been more consistently shown. The 5HT2 antagonist ketanserin has been found to inhibit both provoked and spontaneous attacks of flushing, diarrhea, and dyspnea in a proportion of patients with carcinoid syndrome.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Carcinoid syndrome and serotonin: therapeutic effects of ketanserin. 228 51

The enterochromaffin (EC) cell system is distributed throughout the entire gastrointestinal tract. Enterochromaffin cells are the major source of intestinal serotonin (5-HT), but separate subpopulations of EC cells may synthesize and store peptides as substance P (SP), motilin, and enkephalin as well. Of special interest is that 5-HT and SP, which may coexist in EC cells, have several functional similarities, i.e., inhibition of gastric acid secretion, stimulation of intestinal motility, and secretion of water and electrolytes. Carcinoid tumors are derived from the gut endocrine system. Depending on site of origin, carcinoids are divided into foregut, midgut, and hindgut derivatives with different clinical symptoms. A common biochemical feature of midgut carcinoids is the production of 5-HT and SP. Histochemically, midgut carcinoids are characterized by the argentaffin reaction--a direct reduction of silver salts owing to 5-HT. Specific antisera for the immunocytochemical demonstration of secretory products are available as well. Despite their relative infrequency, carcinoids are the most common small intestinal tumors. The common appendix tumors generally have a benign clinical course, whereas the small intestinal tumors have different growth patterns and frequently metastasize with increasing size, and may thus give rise to the carcinoid syndrome (diarrhea, facial flush, right-sided cardiac valvular disease, and asthma). Carcinoid symptoms first appear when hepatic inactivation of 5-HT is exceeded, unless the carcinoid has an extraintestinal localization, for example, ovarian lesions may elicit symptoms in the absence of hepatic disease owing to direct secretion into systemic circulation.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Serotonin and carcinoid tumors. 241 66

The plasma concentrations of various tachykinins were measured before and during flushing episodes in 16 patients with metastatic carcinoid tumors. The flushing attacks were induced by iv injection of pentagastrin or ingestion of food or alcohol. Tachykinins, such as neurokinin A (NKA) and neuropeptide K (NPK), increased 2-fold during flushing episodes in 12 patients, and the plasma concentrations of substance P increased to a varying extent in 3 patients. Chromatographic analysis of plasma samples taken before and during flushing episodes in 2 patients indicated the presence of individual spectra of tachykinins. In addition, the plasma concentration of tachykinin [TKLI(K12)], using an assay that detects NKA, NPK, kassinin, eledoisin, and NKB, but not substance P and physalaemin, and the urinary excretion of 5-hydroxyindole acetic acid (5-HIAA) were measured in 20 patients with midgut carcinoid tumors before and during treatment with human leucocyte interferon. The overall changes in the 2 tumor markers were concordant in 18 of the 20 patients. Thus, the Spearman correlation coefficient between the percent changes in urinary 5-hydroxyindole acid excretion and plasma TKLI(K12) was 0.54 (P less than 0.001). The patients who had a decrease in the tumor markers also had a decrease in flushing episodes and diarrhea. Plasma TKLI(K12) is a convenient tumor marker for the diagnosis and follow-up of patients with carcinoid tumors of midgut origin. The combined use of both tumor markers strengthens the diagnosis and may improve the evaluation of response during treatment.
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PMID:Tachykinins in carcinoid tumors: their use as a tumor marker and possible role in the carcinoid flush. 242 99

Nine patients with pancreatic apudomas (seven gastrinomas, one glucagonoma, one tumor secreting a substance P-like component) and nine with metastasized carcinoid tumors were treated with a somatostatin analogue (SMS 201-995), administered subcutaneously twice daily for 3 days. Treatment was pursued for 2 to 12 months in nine patients in whom SMS was clinically and/or biologically beneficial. In gastrinomas, SMS decreased plasma gastrin in all but one patient, inhibited the residual gastric acid secretion under H2-blockers and improved diarrhea; in the glucagonoma patient, glucagonemia decreased and skin lesions disappeared. In carcinoid syndrome, clinical efficacy was partial and inconstant; daily 5-hydroxyindole acetic acid (5-HIAA) output was slightly decreased. Plasma substance P levels decreased in six patients with initially high concentrations. No antitumoral activity or side effects have been so far evidenced. SMS 201-995 is a useful, well-tolerated agent in secreting pancreatic apudomas and to a lesser extent in carcinoid syndrome, where high-dosage regimens may be required.
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PMID:Clinical and hormonal effects of a long-acting somatostatin analogue in pancreatic endocrine tumors and in carcinoid syndrome. 243 3

In a prospective study of 103 patients with carcinoid tumors consecutively referred for medical treatment, the most common sites of the primary tumors were the ileum (73%), bronchi (7%), and jejunum (4%). All patients had local metastases, and 96 (93%) also had liver metastases. The most common initial symptoms were diarrhea (32%), ileus (25%), and flush (23%). The overall frequency of diarrhea was 84% and of flush was 75%. Heart insufficiency caused by cardiac valve disease was seen in 33% of the patients. The carcinoid syndrome, including flush, diarrhea, and elevated urinary 5-hydroxyindole acetic acid (5-HIAA) concentrations, was manifested by 69 patients (67%), 64 of whom (93%) had carcinoid tumors of mid-gut origin. Elevated urinary 5-HIAA was found in 91 patients (88%), of which 89 displayed liver metastases. The plasma concentration of the tachykinin neuropeptide K (NPK) was elevated in 67 patients (66%), 63 of whom had tumors of the mid-gut region. Serum pancreatic polypeptide (PP) and human chorionic gonadotrophin alpha levels were elevated in 43% and 28% of the patients, respectively, and the highest levels were found in patients with metastatic bronchial carcinoid tumors. Thirty-nine of the 103 patients are now dead; 18 died of tumor progression, whereas 14 patients died of heart failure secondary to a carcinoid tricuspidal valve insufficiency. The estimated median survival from the time of histologic diagnosis was 14 years, and from the time of carcinoid syndrome was 8 years.
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PMID:Malignant carcinoid tumors. An analysis of 103 patients with regard to tumor localization, hormone production, and survival. 244 Mar 90

Motilin, normally present in a specific cell type in the upper small intestine, is believed to have a physiologic role in initiating the interdigestive migrating motor complex. Motilin may play a pathophysiologic role in the diarrhea in the irritable bowel syndrome, the dumping syndrome, chronic liver disease, and chronic renal failure. Furthermore, increased frequency of bowel movements is an important symptom in patients with the carcinoid syndrome. We have studied 73 patients with metastatic carcinoid tumors with regard to stool frequency and plasma concentration of motilin and neuropeptide K (NPK) and diurnal urinary excretion of 5-hydroxyindoleacetic acid (5-HIAA). Thirty-eight (52%) of the 73 patients had elevated (greater than 126 pmol/l) plasma concentrations of motilin, whereas 59 (81%) of the patients had diarrhea. The increased frequency of bowel motions correlated significantly (p less than 0.01) with the plasma concentrations of motilin, whereas no significant correlation with 5-HIAA and NPK was found. High-performance liquid chromatography of plasma extracts showed a single component eluting in the position of synthetic porcine motilin. However, extracts from five carcinoid tumors did not contain any significant levels of motilin. Carcinoid tumors are known to contain and secrete several biologically active substances such as serotonin, histamine, prostaglandins, and tachykinins, which are likely to cause disturbances of intestinal secretion and motility, which in turn might release motilin from the motilin-containing cells of the small intestine. The increased motilin levels might then participate in a vicious diarrhea circle together with the other agents.
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PMID:Motilin in plasma and tumor tissues from patients with the carcinoid syndrome. Possible involvement in the increased frequency of bowel movements. 244 32


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