Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P01275 (glucagon)
 26,492 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The pathophysiological, biochemical, histological, ultrastructural, and immunohistochemical characters of a case of malignant pancreatic islet cell tumor with watery diarrhea syndrome were carefully investigated. Four hormones or mediators--somatostatin (SST), vasoactive intestinal peptide (VIP), serotonin, and prostaglandin E--were markedly elevated in the circulation. The diagnosis was further confirmed by exploratory laparotomy and autopsy. The contents of SST and VIP in tumor tissues were very high. Gel chromatography of tumor extract revealed single peaks for both SST and VIP. Immunohistochemical studies of tumor tissues showed numerous immunoreactive cells to anti-SST, moderate amount of VIP-positive cells, and a few hCG-, insulin-, and glucagon-positive cells. In conclusion, this is an unusual case of Verner-Morrison syndrome in which three kinds of bioactive hormones or mediators were simultaneously secreted; peptides, amine, and prostaglandin.
 ...
PMID:Watery diarrhea syndrome caused by multihormonal malignant pancreatic islet cell tumor secreting somatostatin, vasoactive intestinal peptide, serotonin, and prostaglandin E--a clinicopathological, biochemical, immunohistochemical, and ultrastructural study. 288 47

Long-acting somatostatin analogues such as SMS 201-995 (Sandoz) are being evaluated in a wide range of clinical indications, including gut neuroendocrine tumours and acrogemaly. Long-term continuous SMS 201-995 treatment has achieved useful symptomatic improvement in diarrhoea in 4 patients with metastatic VIPomas who had relapsed following previous treatment. Clinical improvement has outlasted suppression of VIP secretion (suggesting an additional direct antisecretory action of SMS 201-995) and has occurred despite expansion of hepatic metastases. In 6 patients with tumours secreting gastrin and/or glucagon, secretion of these peptides was acutely inhibited by SMS 201-995. However, endocrine and clinical responses to chronic treatment have been less consistent. SMS 201-995 is active orally at doses of 4-8 mg and when given thrice-daily to 6 patients with active acromegaly, suppressed mean 24-h growth hormone levels by 51-88%. Despite significantly reduced plasma insulin concentrations, glucose tolerance did not deteriorate. SMS 201-995 was also effective in suppressing thyroid-stimulating hormone (TSH) and thyroid hormone secretion in a patient with mild thyrotoxicosis due to non-tumoural inappropriate TSH hypersecretion. In all cases SMS 201-995 treatment has been well tolerated and has few side-effects.
 ...
PMID:Clinical evaluation of SMS 201-995. Long-term treatment in gut neuroendocrine tumours, efficacy of oral administration, and possible use in non-tumoural inappropriate TSH hypersecretion. 289 35

Exocrine pancreatic insufficiency has been observed in some diabetics with peripheral neuropathy and diarrhea. Several mechanisms may be responsible for this insufficiency: (1) pancreatic atrophy, (2) disruption of the cholinergic enteropancreatic reflexes, or (3) elevated serum levels of peptides such as glucagon and pancreatic polypeptide which are known to inhibit pancreatic exocrine secretion. To clarify the mechanism(s) involved in this exocrine pancreatic impairment, we studied 10 diabetics with diarrhea and peripheral neuropathy. Their results were compared to those of eight normal volunteers. Each subject underwent a standardized pancreatic function study which assessed nonstimulated secretion, the response to intrajejunal infusion of a mixture of amino acids, and the output following intravenous administration of secretin and cholecystokinin (CCK). In separate studies, the effect of a background infusion of bethanechol and secretin on the pancreatic response to CCK was assessed in six patients and six normal controls. Compared to normals, all diabetics exhibited a significant reduction in both enzyme and bicarbonate secretion to all stimuli. This reduction was not corrected by administering bethanechol. Plasma glucagon and pancreatic polypeptide levels in diabetics were not significantly higher than those in controls. We conclude that diabetics with diarrhea and peripheral neuropathy exhibit impairment of their exocrine pancreatic secretion and possible mechanisms for this are discussed.
 ...
PMID:Impaired exocrine pancreatic function in diabetics with diarrhea and peripheral neuropathy. 289 72

A case of a 58-year-old woman with an unusual variant of malignant islet-cell tumor showing oncocytic features is described. Using the light microscopy technique, the tumor appeared comprised of solid nests of uniform cells with abundant, eosinophilic cytoplasm and round nuclei with granular chromatin. Ultrastructurally, the cells contained numerous abnormal mitochondria, dilated rough endoplasmic reticulum, and scattered dense-core neurosecretory granules, often associated with cytoplasmic filaments. Tumor cells were focally immunoreactive for insulin, glucagon, and somatostatin and diffusely immunoreactive for alpha 1-antitrypsin as assayed by the avidin--biotin technique. The tumor was immunonegative for human chorionic gonadotropin, gastrin, adrenocorticotropic hormone, and serotonin. The patient exhibited some of the clinical features associated with glucagonoma syndrome, including diabetes mellitus and chronic diarrhea. The tumor behaved in a malignant fashion, with widespread lymphatic involvement and bony metastases at the time of presentation. This report of an oncocytic islet-cell carcinoma supports the concept of oncocytic differentiation in islet-cell tumors in a fashion analagous to oncocytic carcinoids.
 ...
PMID:Functioning oncocytic islet-cell carcinoma. Report of a case with electron-microscopic and immunohistochemical confirmation. 300 44

This study was conducted to determine if macrophage elaborated monokines in general, and human recombinant tumor necrosis factor (hrTNF alpha) in particular alter glucose metabolism in a manner analogous to that observed in endotoxin-treated animals. Endotoxin-tolerant rats were infused for 3 hr with saline, E. coli endotoxin (100 micrograms/l weight) or monokines contained in conditioned media from endotoxin-stimulated RAW 264.7 cells (1 microgram/ml). Compared to saline- and endotoxin-infused rats, animals receiving the monokine mixture had no change in mean arterial blood pressure or heart rate but exhibited overt signs of morbidity including stupor and diarrhea. Monokine-infused rats remained euglycemic but had elevated lactate concentrations and a 15-30% increase in glucose rate of appearance (Ra). Nontolerant rats received a 3 hr infusion of saline, hrTNF alpha (15 micrograms/100 g), or heat-treated hrTNF alpha. HrTNF alpha infusion increased glucose Ra about 25% compared to the two control groups but did so without producing signs of morbidity seen in the monokine infused animals. Serum TNF levels were 6-fold higher in rats infused with the monokine mixture compared to animals infused with hrTNF alpha, and this reflected the different levels of TNF contained in the monokine mixture and hrTNF alpha infusates. Plasma insulin, glucagon, and catecholamine concentrations were increased in rats infused with either the monokine mixture or hrTNF alpha, but the increases were more pronounced in rats receiving the monokine mixture. The results demonstrate that monokines and hrTNF alpha increase glucose production in vivo, and that the effect may be mediated by endocrine changes known to influence glucose homeostasis.
 ...
PMID:Glucose kinetics in rats infused with endotoxin-induced monokines or tumor necrosis factor. 337 Jul 60

The influence of the upper abdominal autonomic denervation on the secretions of insulin (IRI), vasoactive intestinal polypeptide (VIP), secretin, pancreatic glucagon (IRG) and gut glucagon-like immunoreactivity (Gut GLI) was studied. Adult mongrel dogs, which were divided into control, truncal vagotomy and upper abdominal autonomic denervation groups, were investigated by intraduodenal glucose infusion test under general anesthesia. The glucose level and the response of insulin, VIP, secretin, IRG and Gut GLI secretions in the truncal vagotomy group showed no significant difference compared with those in the control group. These findings suggested that the vagus nerve is not concerned largely in the glucose level and in response of insulin VIP, secretin, IRG, and Gut GLI induced by intraduodenal glucose loading. In the upper abdominal denervation group, severe diarrhea was manifested within 60 minutes after the intraduodenal glucose infusion test, and significantly increased responses were shown in secretions of insulin, VIP, secretin, IRG, and Gut GLI. These findings suggested that upper abdominal autonomic denervation acted acceleratory on the secretions of insulin, VIP, secretin, IRG and Gut GLI by intraduodenal glucose infusion test. In addition, it was suggested that dissection of upper abdominal autonomic plexus caused diarrhea after the intraduodenal glucose infusion test.
 ...
PMID:[Influence of upper abdominal autonomic denervation on pancreatic and gut hormone secretion]. 343 38

Experimental studies using dogs were performed to elucidate the participation of gastrointestinal hormones as well as the ileocecal valve in postoperative sequelae following massive small bowel resection. Although in both the ileal resection and the ileocecal resection groups the absorption of fat was reduced postoperatively, body weight tended to increase in the former, while it decreased gradually in the latter. In addition, watery diarrhea persisted after ileocecal resection. Plasma total bile acid concentrations in each group were lower than those before surgery, as were plasma levels of both total glucagon and neurotensin. Although differences were not significant, plasma neurotensin levels tended to be higher after ileocecal resection, but plasma total glucagon levels tended to be lower. Plasma gastric inhibitory polypeptide (GIP) response to butter ingestion was also lower after both ileal and ileocecal resection; especially in the latter case the decrease was significant. These results indicate that the diminished plasma levels of neurotensin, enteroglucagon and GIP may be related to the impairment of adaptive changes in the remaining small intestine.
 ...
PMID:The role of humoral factors and the ileocecal valve in pathological changes occurring after distal small bowel resection. 357 14

Vasoactive intestinal peptide (VIP), originally isolated from hog small intestinal mucosa, has been shown to cause small intestinal secretion. More recently, this peptide has been identified in the plasma and tumors of patients with the so-called "pancreatic cholera" syndrome. In order to explore the possible role of VIP in the pathogenesis of this syndrome, we examined the effects of this peptide and other hormones on the cyclic AMP levels, adenylate cyclase activity, and ion transport in in vitro preparations of ileal mucosa. In rabbit ileal mucosa, VIP (20 mug/ml) caused a prompt fivefold increase in cyclic AMP level, whereas nine other hormones, which have been postulated to cause intestinal secretion, failed to exert such an effect. Pentagastrin and glucagon also failed to increase cyclic AMP levels in canine ileal mucosa. An increase in mucosal cyclic AMP levels was observed at a VIP concentration of 0.1 mug/ml and appeared to be nearly maximal at 2.0 mug/ml. VIP (100 mug/ml) stimulated adenylate cyclase activity in a membrane preparation from rabbit ileal mucosa. Secretin (6.0 x 10(-5) M) failed to do so. When added to the serosal side of isolated rabbit ileal mucosa clamped in an Ussing chamber, VIP (2 mug/ml) increased short-circuit current (SCC) and caused net secretion of both Cl and Na. Net Cl secretion exceeded net Na secretion. These effects of VIP on mucosal cyclic AMP metabolism and ion transport are similar to those observed with cholera enterotoxin and certain prostaglandins. VIP was also tested with normal human ileal mucosa. At a concentration of 2 mug/ml it caused a fivefold increase in cyclic AMP level and an increase in SCC of the same magnitude as that caused by 5 mM theophylline. Addition of a second 2-mug/ml dose of VIP and addition of theophylline after VIP produced no further change in SCC. We conclude the VIP stimulates adenylate cyclase and active ion secretion in both rabbit and human ileal mucosa. This may be related to the pathogenesis of diarrhea in patients with the pancreatic cholera syndrome.
 ...
PMID:Vasoactive intestinal peptide stimulation of adenylate cyclase and active electrolyte secretion in intestinal mucosa. 436 34

Immunocytochemical stains for various pancreatic hormones were performed on 77 pancreatic endocrine tumors from 59 patients [17 with hypoglycemia, three with glucagonoma syndrome, 18 were Zollinger-Ellison syndrome, six with WDHA (watery, diarrhea, hypokalemia, and achlorhydria) syndrome and 15 without endocrine symptoms]. In all tumors that caused either hypoglycemia or glucagonoma syndrome, insulin and glucagon were respectively identified. On the other hand, only 10 tumors from 18 patients with Zollinger-Ellison syndrome were positive for gastrin, and only four of six patients with WDHA syndrome had a vasoactive intestinal peptides-positive tumor. Ten of 15 clinically silent tumors contained hormone-producing cells but without a consistent pattern. Ten neoplasms were negative for all hormones tested. Twenty-six tumors showed positively for more than one hormone and usually one cell type predominated. Four patients had multiple tumors which showed variation in the architecture and cellular composition. The tumors were classified into three major histopathologic groups: solid, gyriform, and glandular. The correlation between the pattern of growth and the hormonal production was generally poor. However, a pure gyriform pattern was often associated with insulin production, and glandular differentiation was commonly seen in tumors associated with Zollinger-Ellison syndrome. This study demonstrates the reliability of the immunocytochemical method for the specific identification of cell types in pancreatic endocrine tumors.
 ...
PMID:Retrospective study of 77 pancreatic endocrine tumors using the immunoperoxidase method. 612 37

The intestinal carcinoid tumors of 26 patients were stained for the presence of serotonin, gastrin, somatostatin, motilin, secretin, glucagon, pancreatic polypeptide, ACTH, and neurotensin. Argentaffin and argyrophil stains were also performed in all cases. Thirty-five separate tumors (counting metastases and multiple primaries) from the 26 patients were studied. Serotonin was present in 30 of the 35 tumors. Nineteen tumors contained serotonin only. Fourteen tumors contained multiple neuroendocrine products. One tumor contained gastrin only. One tumor did not stain immunohistochemically, but was argyrophilic. Metastatic deposits were studied in nine patients. Some metastases produced the identical neuroendocrine products as the primary tumor, whereas others produced either additional or fewer hormones than the primary tumor. Moreover, different metastases from the same primary tumor were observed to produce different hormones. Argyrophilic cells were present in all cases and were much more numerous than cells staining by immunohistochemistry. Argyrophilic cells probably contain monoamines and polypeptide hormones in addition to those studied in this series. The argyrophil stain was the best general stain in this study for the demonstration of neuroendocrine cells. Argentaffin staining was negative in ten cases that were serotonin positive and two argentaffin positive cases were serotonin negative. The carcinoid syndrome, as clinically defined by the presence of flushing and diarrhea, was noted in five patients, all of whom had serotonin-containing small bowel carcinoids. Endocrine-related symptoms were not clinically appreciated in the remaining patients.
 ...
PMID:The neuroendocrine products of intestinal carcinoids. An immunoperoxidase study of 35 carcinoid tumors stained for serotonin and eight polypeptide hormones. 618 28


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>