Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01350 (gastrin)
 9,683 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

There have been new developments in the diagnosis and therapy of Zollinger-Ellison syndrome. The main symptoms of the syndrome are ulcers at atypical sites and nocturnal hypersecretion. Diarrhea and steathorrhea are equally common and may be misinterpreted. Diagnosis is established by the paradoxical rise in plasma gastrin after intravenous secretin provocation. Fasting plasma gastrin levels alone may be misleading and suffer from both false positive and false negative results. Previously, total gastrectomy was necessary to prevent complications. Today the symptoms can be controlled by adequate H2-receptor blocker treatment, if necessary combined with an antimuscarinic drug such as pirenzepine. Exploratory surgical attempts to remove the tumor have a success rate of only 20% and only half of those may be cured. However, the new technique of transhepatic pancreatic vein catheterization, supplemented by determination of local hormone gradients, allows preoperative localization of even small tumors. In the last two years the author has had experience of 5 patients with endocrine tumors of the pancreas (1 insulinoma, 4 gastrinoma) who underwent this procedure. In every case the tumor was localized, removed by surgery and the patients subsequently cured of the syndrome, even including 2 patients with multiple endocrine neoplasia (MEN 1). It is concluded that this chance of cure should be offered to every patient with this syndrome.
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PMID:[Diagnosis and curative therapy in Zollinger-Ellison syndrome]. 240 28

Pancreatic specimens of nine patients suffering from multiple endocrine neoplasia type I (MEN I) were investigated with regard to tumor frequency and growth pattern, islet hyperplasia and endocrine cell neoformation, immunocytochemical hormone profile of the tumors, and correlation to clinical symptoms. The majority of the 201 tumors were microadenomas (diameter less than 0.5 cm), which frequently displayed a trabecular growth pattern. Microadenomatosis was considered the most distinct feature of the MEN I pancreas. Additional larger tumors (diameter greater than 1.0 cm) were found in five patients. Whereas islet hyperplasia appears not to belong to the spectrum of the pancreatic lesions in MEN I, nesidioblastosis was occasionally observed. Immunocytochemical screening revealed that among hormone-positive tumors (approximately 80% of the tumors), pancreatic polypeptide tumors (PPomas), glucagonomas, and insulinomas were the most frequent. The high incidence of PPomas in these pancreases probably accounts for the elevated serum PP levels found in many MEN I patients. Somatostatinomas, gastrinomas, vasoactive intestinal polypeptide tumors (VIPomas), and neurotensinomas were rare. Clinically overt hyperinsulinism, observed in two patients and associated with a large insulinoma, was cured by tumor resection. Eight of nine patients presented a Zollinger-Ellison's syndrome (ZES), but only in two patients were gastrin-producing tumors found. The source of gastrin in MEN I patients with a ZES, in whom no gastrinoma could be detected, remains unclear.
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PMID:Pancreatic lesions and hormonal profile of pancreatic tumors in multiple endocrine neoplasia type I. An immunocytochemical study of nine patients. 242 Apr 39

Sandostatin (SMS 201-995 (SMS)), a potent, long acting analog of native somatostatin was used in five patients with functional endocrine tumors (gastrinoma, two patients; insulinoma, one patient; glucagonoma, one, and adult onset nesidioblastosis, one). Primary and secondary peptide levels were obtained during provocation with a test meal, a calcium infusion, a secretin bolus and either a glucagon or tolbutamide bolus. During provocation test, the levels of the primary peptides insulin and C-peptide (nesidioblastosis and insulinoma), gastrin (gastrinoma), glucagon (glucagonoma) and the secondary peptides calcitonin, gastrointestinal peptide, gastrin releasing peptide, motilin, neurotensin, pancreatic polypeptide, somatostatin, substance-P and vasoactive intestinal peptide were obtained at predetermined intervals and quantitated by radioimmunoassay. SMS therapy was begun and peptide levels were again obtained during provocation. SMS suppressed basal primary peptide levels in all patients by more than 50 per cent. In 23 of 26 provocative tests, SMS effectively decreased circulating peptide levels by more than 50 per cent. Thirteen instances of elevated basal secondary peptides were discovered, and SMS universally suppressed these levels by a mean of 54 per cent. Of the 44 provocative tests performed, elevated secondary peptide levels were present in 41. SMS was effective in 31 of these 41 tests. The mean suppression of these provoked secondary peptide levels was 70 per cent. SMS effectively suppresses both basal and provoked peptides and, thus, provides relief of the clinical symptoms induced by pathologic elevations of primary and secondary peptides.
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PMID:Suppression of primary and secondary peptides with somatostatin analog in the therapy of functional endocrine tumors. 246 Sep 58

Multiple endocrine neoplastic diseases are genetically determined conditions with particular organ patterns for endocrine tumors. In Type I or Wermer's syndrome the endocrine pancreas, anterior pituitary and parathyroids are involved, insulinoma being the most frequent pancreatic tumor. To facilitate diagnosis, a prolonged oral glucose tolerance test, a fasting test and determination of the glucose-insulin ratio are recommended. Localisation is sought by computer tomography and angiography. A gastrinoma is excluded on the basis of normal gastrin levels in serum and by means of the secretin-provocation-test. Pituitary tumors can be classified more closely with prolactin levels and releasing-hormone tests (LH-RH and TRH). Prolactinoma is the most frequent pituitary tumor and amenable to bromocryptin treatment. If Wermer's syndrome is suspected, primary hyperparathyroidism has to be excluded on the basis of calcium and parathormone levels. Chief cell hyperplasia or multiple adenomas are frequent. Surgical resection is necessary.
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PMID:[Type I multiple endocrine neoplasia--Wermer syndrome]. 257 44

As part of a study to manage islet cell tumors in patients with multiple endocrine neoplasia (MEN), patients with MEN I and Zollinger-Ellison syndrome (ZES) underwent surgery if a pancreatic islet cell tumor was identified on imaging studies. Patients with MEN I and either insulinoma or vasoactive intestinal polypeptide tumor (VIPoma) underwent surgery whether or not a tumor was identified. Each patient underwent preoperative portal venous sampling (PVS). Nine patients with MEN I and one with MEN II underwent surgery; seven had ZES, one had insulinoma, one had VIPoma, and one had both insulinoma and ZES. Eight of the nine patients with MEN I had an identifiable hormone gradient on PVS. Islet cell tumors were removed from the pancreas of each patient; two patients also had duodenal wall tumors, and three patients had malignant islet cell tumors. No patient with ZES and MEN I was cured of ZES despite the fact that islet cell tumor was removed from the region of the gastrin gradient in five of six patients. The single patient with MEN II and ZES and the three additional patients with MEN I and either insulinoma or VIPoma were cured by islet cell tumor resection. The results indicate that islet cell tumors in patients with MEN I can be both extrapancreatic and malignant. In patients with MEN I and ZES, ZES cannot be cured by tumor resection, and PVS cannot be used to select patients for curative surgery. It appears that gastrinoma in patients with MEN II, as well as either insulinoma or VIPoma in patients with MEN I, can be cured by islet cell tumor resection.
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PMID:Management of islet cell tumors in patients with multiple endocrine neoplasia: a prospective study. 257 57

The association of gastrin- and insulin-producing tumors of the pancreas is rare. In the 30 years' experience of Zollinger and others, of 40 patients with gastrinoma none had insulin-producing tumors. In contrast to patients with Zollinger-Ellison syndrome, of whom 15% to 26% are classified as having multiple endocrine neoplasias type I (MEN I), only 3% to 4% of patients with insulinomas have other endocrine neoplasms. Insulinomas in patients with MEN I are usually single tumors that usually can be cured with enucleation of the tumor. In contradistinction, gastrinomas in patients with MEN I are diffuse in nature and resection only rarely can be accomplished. Long-term management of gastric hypersecretion is best accomplished by H2-receptor antagonists. If the patient does not respond to H2-receptor antagonists or is unwilling to take the drug indefinitely, he or she will be a candidate for total gastrectomy.
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PMID:Insulinoma and gastrinoma in Wermer's disease (MEN I). 288 84

Twelve islet cell tumors and one islet cell hyperplasia were studied with immunocytochemical and radioimmunoassay methods. With immunocytochemical staining, all six insulinomas, one mixed insulinoma-glucagonoma, and four gastrinomas were positive for insulin, insulin and glucagon, and gastrin, respectively. Pancreatic polypeptide (PP) was positive in three insulinomas and one mixed insulinoma-glucagonoma. All of the tumors were positive for neuron-specific enolase (NSE). Radioimmunoassays of tissue extracts further disclosed that all functioning tumors contained more than one pancreatic hormone. PP concentrations of two insulinomas and one mixed insulinoma-glucagonoma were higher than that of normal control pancreases. A study of protein meal-stimulated PP secretion revealed that three of the insulinoma cases and two gastrinoma cases exhibited higher plasma PP levels than the age-matched controls. The findings suggest that: both functioning and nonfunctioning islet cell tumors derive from neuroendocrine cells positive for NSE; all functioning islet cell tumors appear to contain PP in the tumor tissue as a minor component; as many as 70% of the patients with islet cell tumors present with abnormally higher plasma PP levels after protein meals; and a study of meal-stimulated PP secretion may well be used as a marker for the presence of functional islet cell tumors.
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PMID:Pancreatic polypeptide in islet cell tumors. Morphologic and functional correlations. 299 43

The aim of this retrospective study was to correlate the results of hormonal immunocytochemistry of 46 endocrine tumors to the corresponding clinical syndromes in 24 patients. They were divided as following: 14 cases of insulinoma, 3 cases of Zollinger-Ellison syndrome, 1 case of glucagonoma, 1 case of carcinoid syndrome and 5 cases without any obvious endocrine manifestations. Each tumor was tested with anti-insulin, anti-glucagon, anti-pancreatic polypeptide, anti-vasoactive intestinal peptide, anti-gastrin immune sera according to the peroxidase-antiperoxidase method. The presence of insulin was proved in 13 of 14 cases of insulinomas and the presence of gastrin in 2 of 3 cases of Zollinger-Ellison syndrome. Among the 5 asymptomatic cases, a somatostatinoma and a vipoma were individualized. More than 50 p. 100 of the tumors showed plurihormonal secretion with one predominantly secreted hormone responsible for the clinical syndrome. This study demonstrated the diversity of the hormonal secretion by some tumors and their metastasis in the same patient. Malignant insulinomas correspond either to poorly secreting tumors or to plurihormonal tumors secreting gastrin and glucagon as well.
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PMID:[Hormone immunocytochemical studies of 46 endocrine tumors of the pancreas in 24 patients]. 301 9

Gastrin gene expression was observed in two permanent rat insulinoma (RIN) cell lines derived from a rat insulinoma. Gastrin expression was selective; highest expression was seen in a cell line which did not express other islet cell hormones. Gastrin mRNA transcription initiated from the same promoter as antral gastrin mRNA. DNA transfection studies with a gastrin chloramphenicol acetyltransferase chimeric gene showed higher expression in gastrin-expressing RIN cells than non-gastrin-expressing islet cells. This implies that gastrin-expressing RIN cells selectively express a trans-acting transcriptional activator which binds to cis-acting regulatory sequences within the 5'-flanking DNA sequence and first exon of the gastrin gene. The gastrin peptide precursor synthesized in these RIN cell lines is subject to the same repertoire of posttranslational modifications within the cell's secretory apparatus (endoproteolytic cleavage, tyrosine sulfation, and C-terminal amidation) as seen in antral G cells. Gastrin mRNA levels in these RIN cells were selectively increased by increasing the extracellular calcium concentration. Membrane depolarization also stimulated gastrin mRNA levels, probably through activation of voltage-sensitive calcium channels. Thus, these gastrin-expressing RIN cell lines provide permanent cell lines useful in analyzing the cellular regulation of gastrin gene expression.
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PMID:Gastrin gene expression and regulation in rat islet cell lines. 305 95

A review of 33 patients operated on between 1951 and 1978 for endocrine tumors of the pancreas is presented. The series consists of 25 patients with hyperinsulinism, 6 with the Zollinger-Ellison syndrome, and 2 with the WDHA syndrome. Clinical features and diagnostic problems are discussed. A noticeable feature is that the average time lapse between onset of symptoms and final diagnosis in insulinoma patients has not been significantly reduced during the years covered by this review. This is in spite of the progress made in testing procedures and laboratory methods designed to diagnose hyperinsulinism. Resection of the tumor has been the preferred treatment in insulinoma patients, of whom 22 are still alive. Insulinomas were associated with other endocrinopathies in 3 cases. Patients with the Zollinger-Ellison syndrome had raised serum gastrin levels and increased basal acid output. Four patients are still alive. Two patients had other endocrinopathies. Both patients with the WDHA syndrome died shortly after the operation. One had biochemical evidence of multiple endocrinopathies.
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PMID:Endocrine tumors of the pancreas. 624 58


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