Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0016382 (flushing)
 6,387 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We examined the role of the potent vasoactive kinin substance-P (SP) in flushing derived from various causes. SP was measured in plasma after acetone/ether extraction using an antiserum directed at the carboxy-terminal 5-11 amino acid region of undecapeptide SP. The antiserum had less than 1% cross-reaction with the other neurokinins, neurokinin-A and neuropeptide-K, that derive from the beta-preprotachykinin gene and share carboxy-terminal residues. Basal and pentagastrin-stimulated SP levels were measured in 22 healthy controls, 11 patients with histologically proven carcinoid tumors, 8 patients with tumors other than carcinoid, and 7 patients with idiopathic flushing (IF). Basal SP levels were less than 10 pg/mL in normal subjects. All patients with midgut carcinoid tumors had SP levels greater than 25 pg/mL, as did 7 of 8 patients with noncarcinoid tumors and 5 of 7 patients with IF. Using 50 pg/mL as the cutoff point, the sensitivity was 63% for detection of a tumor, and 100% of nontumor patients were excluded. Pentagastrin administration uniformly induced flushing and caused a rise in SP levels greater than 150 pg/mL in 5 of 10 patients with carcinoid tumors, 3 of 8 with noncarcinoid tumors, and 0 of 7 with IF, i.e. a SP rise of more than 100 pg/mL suggests a tumor. Administration of somatostatin (150 micrograms) 0.5 h before the pentagastrin abolished flushing in all carcinoid patients and reduced SP levels, but not into the normal range. Long term treatment with SMS significantly reduced flushing and lowered SP levels, but did not restore these to normal. We conclude that 90% of patients with carcinoid/noncarcinoid tumor have raised COOH-terminal SP levels. A basal level above 50 pg/mL or a pentagastrin-stimulated rise of more than 100 pg/mL distinguishes carcinoid from IF. The dissociation between SP concentrations and flushing suggests that SP may not be the only kinin involved in the flushing associated with carcinoid tumors.
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PMID:Plasma substance-P in neuroendocrine tumors and idiopathic flushing: the value of pentagastrin stimulation tests and the effects of somatostatin analog. 169 75

Serotonin (5-HT) and substance P (SP) were assayed in peripheral blood in patients with known midgut carcinoids and hepatic metastases. All patients had supranormal basal levels of 5-HT and SP. The clinical and hormonal response was evaluated by two provocation tests, pentagastrin (PG) injection or calcium infusion. Pentagastrin caused flushing and gastrointestinal symptoms and elevated levels of circulating 5-HT, but not of SP. Pretreatment with a 5-HT2 receptor blocking agent (ketanserin) alleviated gastrointestinal symptoms but had no influence on either 5-HT release or PG-induced flushing. Calcium infusion induced carcinoid symptoms in only two of six patients, which were associated with elevated 5-HT levels (whereas elevated SP levels were seen in only one patient). We conclude that 5-HT is important for the development of gastrointestinal symptoms but not of flushing. Ketanserin may alleviate gastrointestinal symptoms but does not influence PG-induced release of 5-HT. Substance P and 5-HT do not seem to share a common release mechanism. It appears that PG testing is superior to calcium infusion as a provocative test in patients with the carcinoid syndrome.
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PMID:The pentagastrin test in the diagnosis of the carcinoid syndrome. 241 67

The levels of 5-hydroxytryptamine (serotonin, 5-HT) and substance P (SP) were assayed (using high performance liquid chromatography-electron capture and radioimmunoassay methods) in the peripheral blood of 17 patients with known mid-gut carcinoids, 16 of whom had hepatic metastases. All patients had supranormal basal levels of 5-HT and SP. The clinical and hormonal changes induced by two provocation tests, intravenous pentagastrin (PG) and calcium infusion, were compared. Pentagastrin caused flushing in all the patients, induced gastrointestinal symptoms in all but one of the patients with hepatic involvement, and universally elevated circulating 5-HT levels. Pretreatment with a 5-HT2-receptor blocking agent, ketanserin, abolished the gastrointestinal effects but had virtually no influence on either 5-HT levels or flushing induced by intravenous pentagastrin. In contrast, calcium infusion induced carcinoid symptoms in only two of six patients, and this was consistently associated with stimulation of circulating serotonin levels. The authors conclude that 1) 5-HT may be responsible for the gastrointestinal symptoms in carcinoid patients, but it does not seem to play any role in flushing; 2) ketanserin may be a useful therapeutic agent in alleviating gastrointestinal symptoms in carcinoid patients; 3) differential responses to PG suggests that SP is released from a site different from that of 5-HT; 4) it is possible that SP may contribute to the mediation of flushing, but it cannot be the sole agent causing this symptom; and 5) the pentagastrin test with measurements of 5-HT levels in peripheral blood seems to be superior to calcium infusion as a provocative test in documenting the diagnosis of carcinoid disease.
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PMID:The pentagastrin test in the diagnosis of the carcinoid syndrome. Blockade of gastrointestinal symptoms by ketanserin. 257 77

Aspirin therapy for patients with systemic mast cell disease (SMCD) decreases the production of prostaglandin D2, which is thought to be a major mediator of flushing. Paradoxically, in 5 to 10% of patients with SMCD, administration of aspirin causes massive mediator release and an anaphylactoid reaction. We attempted aspirin desensitization in a 34-year-old man with SMCD (confirmed by bone marrow biopsy) who was incapacitated by severe flushing episodes and hypotension. His baseline mediator levels of plasma calcitonin, urinary histamine, and urinary N-methyl-imidazoleacetic acid were abnormal. Pentagastrin stimulation increased the plasma level of calcitonin from 47 pg/mL to 130 pg/mL (normal, less than or equal to 110) at 5 minutes. Oral aspirin desensitization was begun; however, after a cumulative dose of 620 mg, an anaphylactoid reaction ensued in conjunction with hypotension, abdominal cramping, and flushing. Coincidentally, 1 hour after the episode, the plasma calcitonin level increased from 37 pg/mL to 540 pg/mL, and the serum tryptase level increased from 1 ng/mL to 3.9 ng/mL. Six hours after the episode, the urine level of histamine increased from 90 micrograms/g creatinine to 337 micrograms/g creatinine, and the urinary N-methylimidazoleacetic acid increased from 32 mg/24 h to 81 mg/24 h. Hence, the patient had increased basal levels of plasma calcitonin that increased substantially during aspirin desensitization and increased to above the upper limit of normal during pentagastrin stimulation. Human mast cells may be capable of producing calcitonin or causing secretion of calcitonin in response to skeletal changes.
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PMID:Increased plasma calcitonin levels in systemic mast cell disease. 793 97