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At least 253 records · Page 14Linked to original sources
PubMed1999

Slow-transit constipation: solitary symptom of a systemic gastrointestinal disease.

INTRODUCTION: Autonomic neuropathy is thought to play a role in the pathogenesis of slow-transit constipation, but other gastrointestinal organs may also be involved, even if they are symptom-free. We investigated whether motility in gastrointestinal organs other than the colon was impaired in patients with slow-transit constipation and whether the autonomic nervous system was involved. METHODS: Twenty-one consecutive patients (18 females; median age, 46 years) with severe chronic constipation (< or = 2 defecations/week and delayed colonic transit time) were studied. Autonomic neuropathy function was tested with esophageal manometry, gastric and gallbladder emptying (fasting and postprandial motility) by ultrasonography, orocecal transit time (H2-breath test), colonic transit time (radiopaque markers), and anorectal volumetric manometry. The integrity of the autonomic nervous system was assessed by a quantitative sweat-spot test for preganglionic and postganglionic fibers, tilt-table test, and Valsalva electrocardiogram R-R ratio. RESULTS: Esophageal manometry showed gastroesophageal reflux or absence of peristalsis in five of the seven patients examined. Gallbladder dysmotility (i.e., increased fasting, postprandial residual volume, or both) was observed in 6 of 14 (43 percent) patients. Gastric emptying was decreased in 13 of 17 (76 percent) patients. Orocecal transit time was delayed in 18 of 20 (90 percent) patients; median transit time was 160 (range, 90-200) minutes. Median colonic transit time was 97 (range, 64-140) hours. Anorectal function showed abnormal rectoanal inhibitory reflex and decreased rectal sensitivity in 11 of 19 (58 percent) patients. Signs of autonomic neuropathy of the sympathetic cholinergic system were found in 14 of 18 (78 percent) patients. Only one of nine patients had vagal abnormalities detected with the Valsalva test and four of five patients with a history of orthostatic hypotension had a positive tilt-table test. CONCLUSIONS: Slow-transit constipation may be associated with impaired function of other gastrointestinal organs. More than 70 percent of patients with slow-transit constipation present some degree of autonomic neuropathy. Severe constipation may be the main complaint in patients with a systemic disease involving several organs and possibly involving the autonomic nervous system. This should be considered in the management of such cases.

Adolescent↗
PubMed1997

Expression of pancreatic digestive enzymes in normal and pathologic epithelial cells of the human gastrointestinal system.

Pancreatic digestive enzymes have rarely been reported in human nonpancreatic organs. We examined their expression in the epithelial cells of the nonpancreatic gastrointestinal organs, looking for pancreatic alpha-amylase, trypsin, chymotrypsin and pancreatic lipase. Western blotting, enzyme assay and pancreatic alpha-amylase mRNA were also used in selected specimens. In normal tissues, immunoreactivity of one or more of these enzymes was frequently noted in cells of the salivary glands, stomach, duodenum, large pancreatic ducts, extrahepatic bile ducts and gall bladder. The epithelium of the normal oesophagus, small intestine and colon were consistently negative for these enzymes. In pathologic tissues, immunoreactivity for one or more enzymes was present in epithelial cells of pleomorphic adenomas of the salivary glands, oesophageal squamous cell carcinoma, gastric adenoma and adenocarcinoma, pancreatic adenocarcinoma, cholecystitis, adenocarcinoma of the gall bladder and extrahepatic bile duct, and colon adenoma and adenocarcinoma. Western blotting showed a specific band of each enzyme in some specimens of normal stomach. In situ hybridization for pancreatic alpha-amylase mRNA showed specific signals in the normal stomach, but not in the normal colon. Reverse transcriptase polymerase chain reaction analysis for pancreatic alpha-amylase mRNA revealed specific signals in the normal stomach. Enzyme assay revealed that the stomach and gall bladder showed these activities. The data suggest that pancreatic digestive enzymes are produced by several epithelial cell types of the nonpancreatic gastrointestinal organs, that the organs positive for pancreatic enzyme have a common cell lineage, and that neoplasms continue to express or neoexpress these enzymes after neoplastic transformation.

Adult↗
PubMed1987

On the biologically active structures of cholecystokinin, little gastrin, and enkephalin in the gastrointestinal system.

The biologically active conformations of a series of four peptides [four cholecystokinin (CCK)-related peptides and enkephalin] in their interactions with gastrointestinal receptors have been deduced using conformational computational analysis. The two peptides that interact exclusively with peripheral-type CCK receptors are the heptapeptide COOH-terminal fragment from CCK (CCK-7) and the analogous sequence from cerulein (CER-7) in which threonine replaces the methionine proximal to the NH2 terminus. The two peptides that interact exclusively with the gastrin receptor in the stomach are the active COOH-terminal fragment of little gastrin and the COOH-terminal tetrapeptide sequence common to all of these peptides, CCK-4. We find that preferred conformations for the peripherally active peptides CCK-7 and CER-7 are principally beta-bends, whereas little gastrin and CCK-4 are fundamentally helical. In the class of lowest energy structures for both CCK-7 and CER-7, the aromatic rings of the tyrosine and phenylalanine lie close to one another whereas the tryptophan indole ring points in the opposite direction. This structure is superimposable on the structures of a set of rigid indolyl benzodiazepine derivatives that interact with complete specificity and high affinity with peripheral CCK receptors further suggesting that the computed beta-bends are the biologically active conformation. The biologically active conformation for CCK-4 and the little gastrin hexapeptide has also been deduced. By excluding conformations common to CCK-7 and CCK-4, which do not bond to each other's receptors, and then by selecting conformations in common to CCK-4 and the gastrin-related hexapeptide, which do bind to each other's receptors, we deduce that the biologically active conformation at the gastrin receptor is partly helical and one in which the indole of tryptophan and the aromatic ring of phenylalanine are close to one another while the methionine and aspartic acid side chains point in the opposite direction. These major differences in preferred structures between the common CCK-7/CER-7 peptides and the common CCK-4/little gastrin peptides explain the mutually exclusive activities of these two sets of peptides. We have observed that [Met]enkephalin strongly antagonizes the action of the naturally occurring peripherally active CCK-8 (CCK-7 with an NH2-terminal aspartic acid residue added). The computed lowest energy structures for this opiate peptide closely resemble key features of the computed CCK-7/CER-7 structure, further supporting the proposed structure.

Amino Acid Sequence↗
PubMed1984

[Diabetic neuropathy. II. Autonomic neuropathy. The gastrointestinal system].

Autonomic diabetic neuropathy of the alimentary canal takes several basic forms: a) oesophagopathy , b) gastroparesis, c) enteropathy, d) bile duct disorders. In many cases three are no subjective symptoms. In other the onset of the clinical condition may take acute and dangerous forms as in gastropathy. In still other cases e.g. enteropathy, the neuropathy may develop in bizarre and unexpected ways which are highly damaging to the patient's quality of life though in most cases they are not fatal. Bile disorders involving minimal motility after stimulus, as in denervation and reduced sensitivity to pain are particularly significant. Diabetics are more likely to suffer from calculosis (59.6% of cases), with septic complications (20% in diabetics compared to 7.8% in non-diabetics) or cholestasis (20% in diabetics v. 15.8% in non-diabetics). These figures indicate that all diabetics and especially the elderly should be subjected to careful examination to identify any bile disorders.

Cholelithiasis↗