Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0038358 (gastric ulcer)
 5,179 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Sulfated gastrins resemble cholecystokinins (CCK) both structurally and functionally. They are less potent than CCK in stimulating gallbladder contraction and pancreatic enzyme secretion, but the plasma concentrations of sulfated gastrin are higher than those of CCK. Therefore, sulfated gastrins may contribute significantly to the endogenous CCK activity. The degree of sulfation of gastrin differs with the localization in the digestive tract. In the antrum and duodenum of normal subjects 45% of the gastrins are sulfated, as in serum. In contrast, the sulfation of gastrin is complete in the jejunum (human) and in the pancreas (rat and cat). Hence, the degree of sulfation of gastrin is similar to that of CCK in the jejunum. The degree of sulfation in antrum, duodenum and serum diminishes with hypergastrinemia, and is thus significantly lower in patients with gastric ulcer or pernicious anemia than in healthy subjects. In the Zollinger-Ellison syndrome, the degree of sulfation of gastrin varies greatly (20-90%) and the distribution between small and large gastrins is equally variable. However, sulfation and proteolytic processing follows a parallel course; complete processing to smaller components is accompanied by complete sulfation of the peptide and vice versa. During ontogenesis sulfated gastrins may be of special importance, since they are the only sulfated members of the gastrin/CCK family of peptides which occur in substantial quantities in the early fetus. Tyrosine-O-sulfation has now been recognized as a widespread modification, and sulfated tyrosyl residues in gastrin, CCK and leu-enkephalin are examples of a derivatization which can govern the biological activity of regulatory peptides.
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PMID:Measurement and occurrence of sulfated gastrins. 638 82

Acute cold stress caused lesions of gastric mucosa as a result of its attack by active oxygen and nitrogen compounds. The tissue regeneration is regulated by a cascade of tyrosine protein kinases. Gastric ulceration leads to a decrease in activity of tyrosine protein kinases and phosphatases, following by fall in phosphotyrosine content in proteins of plasma membranes of gastric mucosa cells. No changes in superoxide dismutase activity, slight increase in catalase activity, inhibition of glutathione peroxydase, significant increase in OH* content and decrease in zinc level were observed in the gastric mucosa cells of stressed rats. That increased oxidative damage can lead to inactivation of protein tyrosine phosphatases. Nitric oxide synthase activity was three times higher in gastric mucosa cells after the cold stress. That can promote nitrosylation of tyrosine residues. During following days nitric oxide synthase activity remains high. Superoxide dismutase is activated on the 4 and 5th day after the stress. Catalase activity normalizes after second day. Tyrosine protein kinase activity increases in membranes with maximum on the 4th day, and remains inhibited in cytosole. Tyrosine protein phosphatases keep inhibited as well. Gluthatione peroxydase activity and zinc level decreased on the 5th day. Obtained results can be the evidence of violations in signal transduction through protein tyrosine kinase cascades, due to the reduction in tyrosine phosphorylation, as a result of increase in the content of active oxygen and nitrogen species.
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PMID:[Functioning of tyrosine protein kinases and phosphatases in gastric mucosa cells under conditions of oxidative and nitrosative stress in gastric lesions]. 1924 21