Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0007095 (carcinoid)
 6,990 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We describe a method for determination of urinary 5-hydroxyindole-3-acetic acid, a metabolite of serotonin and tryptophan and a useful indicator of metastasizing carcinoid tumor. The analysis is based on the color development with ferric chloride added to the residue obtained on evaporating a diethyl ether extract of the sample that has been acidified with sulfuric acid and saturated with sodium chloride. The color is measured by 510 nm. The reaction was made highly specific by the acidification so that nonspecific reactions with catecholamines and with other phenolic compounds such as salicylic acid could be eliminated.
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PMID:Simple determination of high urinary excretion of 5-hydroxyindole-3-acetic acid with ferric chloride. 61 46

We have suggested the determination of different indolic metabolites of tryptophan: OH 5 trptophan (5 HTP), OH 5 tryptamine (5 HT), OH 5 indolyl-acetic acid (5 HIA) by column chromatography on cationic coupled with spectrofluorimetry after amplification obtained with o-phtaldehyde. The different metabolites are determined alone or simultaneously depending on the buffer used. The following qualitates are examined: sensitivity, specificity, accuracy. We have established normal reference values. For 5 HTP the normal values in urine are less than or equal to 50 microgram per day. In 12 cases of carcinoid tumors we have measured 5 HIA, 5 HTP, 5 HT and calculated the ratio between 5 HT and 5 HTP in the urine which makes it possible to have an idea of the enzyme activity in the hydroxyindol pathway in cases of intestinal and bronkial carcinoids.
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PMID:Determination of OH 5 tryptophan by chromato-spectrofluorimetry in carcinoid tumors. 108 92

Twenty-two patients with advanced metastatic carcinoid disease, most of whom were moribund were subjected to oral administration of 200 mg of 5-fluorotryptophan three times daily. Seven patients died from complications of the tumor before completing the course of one year's treatment. Of the fifteen patients who survived long enough to complete the year of therapy, the average additional survival time was 2.3 years, varying from one to over nine years. The average survival time after the diagnosis of advanced metastatic carcinoid disease was made and prior to the initiation of treatment with 5-fluorotryptophan in these patients was 5.5 years, varying from one to eight years. Side effects of the analog were limited to gastric upset in one patient only. The control of serotonin production and its associated symptoms was considered excellent. Slowly progressive tumor growth led ultimately to death in thirteen of the fifteen patients which was considered due to mechanical factors and not to hormone abnormalities. Two patients continue to survive with good quality of life nine and six years, respectively, after analog therapy. Life in patients with advanced metastatic carcinoid disease has been extended with good to excellent quality by the simple oral administration of the tryptophan analog, 5-fluorotryptophan. Tumor growth does not seem to have been affected by the analog.
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PMID:Carcinoid tumor metastases. Prospective study of twenty-two patients. 120 Feb 95

We evaluated the effect of intravenous (i.v.) glucose on the plasma tryptophan (TRP) and tyrosine (TYR) concentration of 12 normal subjects, six patients with carcinoid tumors and the carcinoid syndrome (carcinoid syndrome), and five patients with carcinoid tumors without the carcinoid syndrome (tumor.) Following i.v. glucose administration, the plasma Trp concentration of the normal subjects and the tumor patients incresed, while the plasma Trp concentration of the carcinoid syndrome patients decreased. Following i.v. glucose administration, the plasma Tyr concentration of the normal subjects and the tumor patients decreased, while the plasma Tyr concentration of the carcinoid syndrome patients did not change. The response to i.v. insulin differed in some respects from the response to i.v. glucose: the plasma Trp of normal subjects did not change while the plasma Trp of carcinoid syndrome patients decreased; the plasma Tyr of the normal subjects increased while the plasma Tyr concentration of the carcinoid syndrome patients did not change. The carcinoid syndrome patients had high serum serotonin concentrations and impaired glucose tolerance and insulin secretion as compared to both normal subjects and tumor patients. We conclude that under appropriate experimental conditions, glucose administration can increase the plasma Trp concentration of normal human subjects.
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PMID:Effect of intravenous glucose and insulin on plasma tryptophan and tyrosine concentrations in normal subjects and patients with carcinoid tumors. 124 11

Deficiency of tryptophan with elevated serum serotonin and liver dysfunction are the prerequisites for the experimental production of cardiac lesions in the guinea pig model of carcinoid syndrome. To apply the above principles in human subjects with carcinoid disease, various indole markers were compared in patients with or without heart involvement, to a group of normal subjects. In the present study, plasma tryptophan (T), serotonin (5HT), and urinary 5 hydroxyindoleacetic acid (5HIAA) measurements were made in 18 (group 1) patients with carcinoid syndrome and 24 normal individuals (group 2). Of the 18 patients, seven (group 1A) had valvular involvement and 11 (group 1B) had none, as determined by clinical, roentgenographic, and echocardiographic (M-mode and 2-D) techniques. Analysis of the above data shows that unlike animal models, there is no difference in serum tryptophan, serum serotonin, and urinary 5 hydroxyindoleacetic acid levels, in patients with carcinoid syndrome with or without cardiac involvement (p greater than 0.05). Furthermore, the data confirm that serum tryptophan, a substrate in carcinoid syndrome, is decreased and in serum serotonin and urinary 5 hydroxyindoleacetic acid, the metabolites are elevated.
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PMID:Do indole markers predict carcinoid heart disease? 242 76

Development of a rapid and sensitive radioassay has permitted study of the conversion of tryptophan to 5-hydroxytryptophan in mammalian tissues. Of normal tissues examined, beef and rat pineal gland contained the highest activity. This is the first direct demonstration of tryptophan hydroxylase in this hydroxyindole-rich tissue. Rat and rabbit brainstem and human carcinoid tumor also had quantities of enzyme that could be measured easily. The reaction requires a reduced pteridine and oxygen and is inhibired by Para-Chorophenylalanine.
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PMID:Tryptophan hydroxylation: measurement in pineal gland, brainstem, and carcinoid tumor. 601 30

The levels of TRP, 5-HTP, 5-HT and 5-HIAA were measured in the proximal colon of the rabbit using ion exchange chromatography and spectrofluorimetry. Assays were performed on fragments of the intact colonic wall, on the muscle layers containing nerve plexuses, and on the mucosa-containing enterochromaffin cells. In spite of identical TRP concentration, 5-HT levels were higher in the mucosa than in the muscle containing nerve plexus. In the muscle, the ratio 5-HIAA/5-HT was about 1, i.e., comparable to that of the brain, whereas the ratio was very low in the mucosa, suggesting a weak 5-HT catabolism in the enterochromaffin cells. When the mucosa was severed from the muscle, 5-HT synthesis was increased. In this case, 5-HT and 5-HIAA concentrations in the reconstituted wall (muscles + mucosa) were higher than in the intact wall. In in vitro studies, levels of newly synthesized (3H)5-HT from (3H)TRP were 3 times higher in the reconstituted wall than in the intact one, and the conversion index of TRP to 5-HT was higher in the mucosa and in the reconstituted wall respectively. These results suggest that enterochromaffin cells do synthesize 5-HT from TRP when the mucosa is divided from the muscle. (3H)5-HT was taken up by both nerve plexuses and mucosa, with a high affinity mechanism. Results from tryptophan loading experiments indicated that 5-HTP decarboxylase in the gut might be involved in the regulation of 5-HT synthesis. The mucosa severed from the muscles might represent a good model for the study of carcinoid tumour development.
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PMID:5-HT metabolism in the intestinal wall of the rabbit. 616 29

A 56-year-old woman was admitted with carcinoid crisis and became comatose. Blood tryptophan at this stage was 5 micrograms/ml; after treatment with 3.4 g tryptophan daily her level of consciousness improved and blood tryptophan increased to 10 micrograms/ml. The carcinoid syndrome was not exacerbated by tryptophan. Tryptophan may have a supportive role in the management of carcinoid crisis.
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PMID:Tryptophan in the treatment of carcinoid crisis. 618 96

We have developed a routine capillary gas-chromatographic profiling method for simultaneous quantitative determination of the tert-butyldimethylsilyl derivatives of homovanillic acid, vanilmandelic acid, 3-methoxy-4-hydroxyphenylethylene glycol, and 3,4-dihydroxyphenylacetic acid and the estimation of 5-hydroxyindole-3-acetic acid in urine. The method is useful for diagnosis and followup of patients with functional tumors characterized by increased urinary excretion of metabolites originating from the metabolism of tyrosine and tryptophan--e.g., neuroblastoma, pheochromocytoma, carcinoid, and melanoma. It may also be applicable in pharmacokinetic studies of administered aromatic amino acids (parkinsonism, mental diseases, loading tests) and for diagnosis and followup of patients with inborn errors of metabolism that are characterized by organic aciduria (for instance, tyrosyluria and phenylketonuria).
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PMID:Simultaneous determination of the four major catecholamine metabolites and estimation of a serotonin metabolite in urine by capillary gas chromatography of their tert-butyldimethylsilyl derivatives. 746 Feb 71

A high performance liquid chromatographic method with quaternary gradient elution and fluorometric detection was developed for profiling of tryptophan (TRP), 5-hydroxytryptophan, serotonin (5-HT) and 5-hydroxyindole-3-acetic acid (5-HIAA) in urine, platelet-rich plasma and (tumour) tissue of patients with carcinoid tumours. Prior to injection, urine samples were diluted and filtered. Platelet-rich plasma and tissue homogenates were prepurified by C18 solid phase extraction. Detection limits were approx. 2 pmol. Results of urinary 5-HT and 5-HIAA compared favourably with those of single component analyses. No consistent diurnal variations were found for TRP, 5-HT and 5-HIAA in 12-h urine samples from 15 healthy adults. Abstinence of 5-HT-rich foods reduced urinary levels of 5-HT and 5-HIAA. C18 extraction of indoles from protein-containing matrices was studied in platelet-rich plasma. Although time-consuming and complicated for daily routine use, the present approach offers particular advantages over single component analyses in the study of TRP metabolism in patients with carcinoid tumours.
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PMID:High performance liquid chromatographic profiling of tryptophan and related indoles in body fluids and tissues of carcinoid patients. 751 1


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