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)

The concentrations of monoamines and various neuropeptides were determined in the hypothalamus of brains from patients with Alzheimer's disease and vascular dementia (n = 26) and compared with control values (n = 21). Decreased concentrations of 5-hydroxyindoleacetic acid (P less than 0.05) and homovanillic acid (P less than 0.01) were found, and increased arginine vasopressin- (P less than 0.01), galanin- (P less than 0.05) and somatostatin- (P less than 0.01) like immunoreactivity. It is proposed that this disequilibrium may be important for certain circadian symptoms, e.g. the changes in sleep/wake rhythms that are rather often observed in dementia.
 ...
PMID:Hypothalamic monoamines and neuropeptides in dementia. 182 5

A case of metastatic carcinoid tumor in the right occipital lobe originating from a primary tumor in the right colon is reported in a 68-year-old man. The tumor had a high bromodeoxyuridine labeling index. Although immunohistochemical studies of the tumor specimen showed positive reactivity for serotonin and somatostatin, blood levels of serotonin and urinary 5-hydroxyindoleacetic acid content were normal. This suggests that coexistence of somatostatin with serotonin in the tumor tissue might lead to inhibition of serotonin release by "autocrine regulation." The neurological complications of carcinoid tumors, including intracranial metastasis, are discussed briefly.
 ...
PMID:Metastatic intracranial carcinoid with immunohistochemical observation. Case report. 197 87

In vivo voltammetry involves the electrochemical detection of central oxidisable substances in situ. In association with this technique micro carbon fibre electrodes (CFE) are able to separate ascorbic acid (Peak 1) from 3,4-dihydroxyphenylacetic acid (DOPAC) plus dopamine (DA) (Peak 2) and 5-hydroxyindoleacetic acid (5-HIAAA) plus serotonin (5-HT) (Peak 3) in vitro. In vivo these biosensors detect the amine metabolites, due to their high extracellular concentration (microM) compared to the amines (nM). In addition homovanillic acid (HVA) (or 3-methoxytyramine (3-MT) in pargyline-pretreated mice) (Peak 4) and somatostatin (Peak 5) were also measured in vivo. However, potassium-stimulated release of DA has been directly monitored in pargyline pretreated mice. In addition, low concentrations (nM) of DA and 5-HT can now be selectively monitored in vitro with new biosensors coated with Nafion which repels negatively charged species including acid metabolites. In vivo, the combination of the Nafion-CFE and normal CFE allowed simultaneous measurements of release and metabolism of 5-HT, respectively. This permitted the observation that changes in 5-HT release are not necessarily reflected by changes in 5-HIAA levels. At present we are developing a Nafion biosensor to monitor basal extracellular DA. Electron microscope studies have shown radical modifications in the surface and structure of carbon fibres following chemical and electrical pretreatments, which may be involved in the development of sensitivity and selectivity displayed by the pretreated CFE towards electroactive compounds. A new approach for selective detection of neuroamines is the analysis of their stimulated fluorescence using LASER. In vitro, the fluorescence of 5-HT is in fact clearly distinguishable from that of 5-HIAA. The feasibility of this methodology in vivo using fiber optic probes will be explored.
 ...
PMID:In vivo voltammetry with micro-biosensors for analysis of neurotransmitter release and metabolism. 197 51

The long-acting somatostatin analogue SMS 201-995 has been used efficaciously in the therapy of metastatic carcinoid tumor, vasoactive intestinal peptide producing islet cell carcinoma, acromegaly, and TSH secreting pituitary tumors. We report the development of a gallstone in a patient treated for 23 months with a long acting somatostatin analogue for a metastatic carcinoid tumor. Symptomatic improvement and a reduction in the urinary excretion of 5-hydroxyindoleacetic acid occurred. There was no evidence of a gallstone on ultrasound and CT scan of the abdomen prior to somatostatin therapy. A progressively enlarging, asymptomatic gallstone developed during therapy.
 ...
PMID:Chronic treatment with a long-acting somatostatin analogue in a patient with intestinal carcinoid tumor: occurrence of cholelithiasis. 231 10

The thiol reagent cysteamine was administered to adult male rats with the aim of investigating its effect on different neural and pineal components. As expected, immunoreactive somatostatin decreased in the median eminence (ME) (p less than 0.05) and gastric antrum (p less than 0.05) after cysteamine; however, no significant change was observed in the pineal IRS content after drug treatment. A decrease in norepinephrine was observed in the ME (p less than 0.001), hypothalamus (p less than 0.001) and pineal gland (p less than 0.05), together with a rise in ME (p less than 0.005) and hypothalamic dopamine (p less than 0.005) content; these results are consistent with a dopamine-beta-hydroxylase inhibiting effect of cysteamine. No effect was observed on hypothalamic serotonin and 5-hydroxyindole-acetic acid content. Pineal N-acetyltransferase (NAT) activity was significantly higher (p less than 0.05) after cysteamine than after saline, but no statistically significant effect was observed on pineal melatonin content. The mechanism involved in the NAT rise is presumably not related to the known stimulatory effect of norepinephrine, which fell after cysteamine. It is suggested that cysteamine may act at an intracellular level, inhibiting NAT degradation, an effect demonstrated in vitro and thought to be related to a thiol:disulfide exchange mechanism.
 ...
PMID:Cysteamine effects on somatostatin, catecholamines, pineal NAT and melatonin in rats. 242

We studied the effects of a long-acting analogue of somatostatin (SMS 201-995, Sandoz) in 25 patients with histologically proved metastatic carcinoid tumors and the carcinoid syndrome. This drug was self-administered by subcutaneous injection at a dose of 150 micrograms three times daily. Flushing and diarrhea associated with the syndrome were promptly relieved in 22 patients. All 25 patients had an elevated 24-hour urinary excretion of 5-hydroxyindoleacetic acid (5-HIAA) (mean, 265 mg per 24 hours; range, 14 to 1079), which served as an objective indicator of disease activity. Eighteen of the 25 patients (72 percent) had a decrease of 50 percent or more in their urinary 5-HIAA levels, as compared with the pretreatment values. The median duration of this biochemical response was more than 12 months (range, 1 to greater than 18). Since no serious toxicity was observed, we conclude that SMS 201-995 may be appropriate for use as early therapy in patients with symptoms due to the carcinoid syndrome who have not responded to simpler measures.
 ...
PMID:Treatment of the malignant carcinoid syndrome. Evaluation of a long-acting somatostatin analogue. 242 48

The plasma concentrations of neuropeptides (neurotensin, substance P, motilin, somatostatin, vasoactive intestinal peptide and gastrin-releasing peptide), the urinary excretion of 5-hydroxyindoleacetic acid and serotonin, and the platelet concentration of serotonin were compared in 133 patients who could be assigned to one of four groups. These groups were as follows: carcinoid tumors present; history of carcinoid tumors; miscellaneous tumors present; and non-tumor diseases. The test with the most sensitivity (i.e., patients with carcinoid tumors labeled positive) and the test with the most specificity (i.e., patients without carcinoid tumors labeled negative) for the presence of carcinoid tumors was determined. Urinary 5-hydroxyindoleacetic acid excretion had a sensitivity of 73 percent and a specificity of 100 percent; the plasma concentration of substance P had a sensitivity of 32 percent and a specificity of 85 percent; and the plasma concentration of neurotensin had a sensitivity of 41 percent and a specificity of 60 percent. Even when basal plasma concentrations of substance P and neurotensin were elevated, there was no additional increase of these neuropeptides prior to ethanol-induced facial flushing. Although measurements of plasma neuropeptide levels may be helpful in occasional patients with carcinoid tumors, it is concluded that measurements of serotonin overproduction--such as 5-hydroxyindoleacetic acid excretion--are of more general value.
 ...
PMID:Role of neuropeptides and serotonin in the diagnosis of carcinoid tumors. 243 80

Levels of somatostatin, noradrenaline, dopamine, 5-hydroxytryptamine and 5-hydroxyindoleacetic acid were unchanged in rat neocortex 3 or 6 months after ibotenic acid lesion of the ipsilateral nucleus basalis that reduced cortical choline acetyltransferase levels by over 60%. These results render unlikely the possibility that non-cholinergic neurotransmitter deficits in Alzheimer's disease cortex are the consequence of cholinergic degeneration.
 ...
PMID:Maintenance of cortical somatostatin and monoamine levels in the rat does not require intact cholinergic innervation. 243 18

The Wobbler mouse (wr) is a mutant that exhibits loss of anterior horn cells in the spinal cord and brainstem and subsequent muscle wasting, particularly of the forelimbs and neck. The wr mice, 2-3 months of age, were found to have increased levels of immunoreactive-thyrotrophin-releasing hormone (ir-TRH) in the spinal cord and pons and medulla, but not in other CNS areas. This increase was observed in dorsal and ventral cord and at cervical, thoracic, and lumbar levels and was confirmed by HPLC to be authentic TRH. The levels of immunoreactive-somatostatin, -neurotensin, and -substance P were not raised in the CNS of wr mice. The activities of two peptidases capable of degrading TRH, pyroglutamylaminopeptidase (PGAP, EC 3.4.11.8) and proline endopeptidase (PEP, EC 3.4.21.26), and the level of 5-hydroxyindoleacetic acid were also raised in the spinal cord of 2-3-month-old wr mice although the activities of alanine aminopeptidase and lactate dehydrogenase and the level of 5-hydroxytryptamine were not. Increased spinal cord levels of ir-TRH and PGAP and PEP activities were not observed in the 1-month-old wr mice. In addition, a pilot study using spinal cord obtained at autopsy from three patients with motor neurone disease and 12 control subjects indicated no increase in spinal cord ir-TRH, PGAP, or PEP in human motor neurone disease.
 ...
PMID:Raised thyrotrophin-releasing hormone, pyroglutamylamino peptidase, and proline endopeptidase are present in the spinal cord of wobbler mice but not in human motor neurone disease. 244 4

Patients with midgut carcinoids undergoing surgical resection or ischemic treatment of hepatic metastases by embolization are at risk for development of carcinoid crises due to release of hormonally active tumor products. Eight such patients were treated on nine separate occasions with increasing subcutaneous doses of a synthetic somatostatin analogue (SMS 201-995) 4 days prior to surgery or hepatic arterial embolization. The patients were tested by pentagastrin provocation and simultaneous measurement of serotonin (5-HT) levels in peripheral blood before and after prophylactic treatment, to evaluate the efficacy of SMS 201-995. The provoked release of 5-HT was markedly diminished, and the basal levels of 5-HT were markedly reduced in patients with high initial levels. During surgery or embolization both SMS 201-995, as well as ketanserin, a 5-HT2 receptor blocker, were given. With this combined treatment all patients were hemodynamically stable during surgery or embolization. During embolization the arterial levels of 5-HT increased only moderately, while urinary excretion of 5-hydroxyindoleacetic acid remained unchanged despite a proven adequate embolization. Two patients were operated on without previous treatment with SMS 201-995; both developed severe crises at induction of anesthesia, but IV SMS 201-995 rapidly reversed the bronchoconstriction and facial flush and gradually restored arterial blood pressure, even though cardiac output remained depressed for a prolonged period. The crisis reaction correlated well with high circulating levels of 5-HT, but after treatment with SMS 201-995 these levels were still high.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:SMS 201-995 and provocation tests in preparation of patients with carcinoids for surgery or hepatic arterial embolization. 246 65


<< Previous 1 2 3 4 5 6 7 Next >>