摘要:

This article reports on Steatorrhea, daily food intake, and fecal substances other than fecal fat (e.g., neutral sterols, bile acids, short-chain fatty acids) in pancreatic exocrine dysfunction arising from chronic pancreatitis (CP) in Japanese, European, and American patients. Changes in upper small intestinal pH and lipase secretion, plasma fatty acid profiles, serum fat-soluble vitamin levels and symptoms of their deficiency, and nutritional status are discussed in detail. Treatment of pancreatic Steatorrhea is described. Throughout this study, we compared characteristics of maldigestion and malabsorption in these patient populations and our study revealed that fecal fat excretion reflected quantitative differences in fat consumption, plasma fatty acid profiles reflected quantitative and qualitative differences in fish oil consumption, and there were no differences in pancreatic exocrine dysfunction among these three groups. Since differences in fecal fat excretion and plasma fatty acid profiles appear to depend on dietary fats, the pathology and treatment of CP patients should be evaluated and the findings used to prescribe treatments.

ISSN:0885-3177    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

The pathogenesis of chronic pancreatitis (CP) has been debated as to whether it is a de novo process or the consequence of acute pancreatitis (AP). We investigated whether recurrent AP in rats leads to CP, by sequential morphological and biochemical studies. Thirty male Wistar rats were fed a choline-deficient diet with intraperitoneal ethionine injections twice daily at a dose of 60 mg/100 g body weight twice weekly, and six rats were killed at 4, 6, and 8 weeks; the remaining 12 rats, followed without further treatment, were killed at 12 and 16 weeks. The pancreata from study and control groups were examined by histology, immunohistochemistry, and bio- and immunoassays. Histologically, moderate to severe intra- and perilobular fibrosis and other CP-like lesions appeared maximally at 8 weeks. Immunohistochemically, the earliest extracellular matrix change was strong fibronectin staining at 4 weeks, with a progressive increase to 8 weeks. Collagens I and III came to show strong, and collagen IV moderate, interstitial staining at 6–8 weeks. These morphological changes, however, returned to nearly normal at 16 weeks. Prolyl hydroxylase was significantly elevated at 4 and 6 weeks and normalized after 8 weeks, with no significant change in collagenase. In conclusion, our results suggest that even severe CP-like lesions induced by recurrent AP are reversible in the absence of persistently elevated prolyl hydroxylase and/or suppressed collagenase. The mechanism regulating these changes remains to be studied further.

ISSN:0885-3177    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

Glutathione is essential for cellular cytoprotection, and in the exocrine pancreas, it is required for digestive enzyme synthesis. The purpose of these studies was to measure the capacity of the exocrine pancreas to synthesize glutathione, determine whether the pancreatic transsulfuration pathway has a role in providing cysteine needed for glutathione synthesis, and determine whether the glutathione synthetic capacity of the pancreas responds to pathologically relevant stresses. The activity of γ-glutamylcysteine synthetase, the key regulatory enzyme for glutathione synthesis, was 3.56 ± 0.29 mU/mg protein in the pancreas of fed rats, compared to 31 ± 4 in the liver and 116 ± 5 in the kidney. Studies using dispersed rat pancreatic acinar cells showed that the exocrine pancreas synthesizes glutathione from precursor amino acids and that the transsulfuration pathway is functionally intact in the pancreas and may serve as an important source of pancreatic cysteine. In mice, pancreatic γ-glutamylcysteine synthetase activity was induced 37% by corn oil, 77% by ethanol, and 88% by both treatments. Thus, the glutathione synthetic capacity of the pancreas is quantitatively less than that of the kidney or liver, but its key regulatory enzyme responds dynamically to pathologically relevant metabolic stresses, suggesting that glutathione is a key pancreatic cytoprotectant.

ISSN:0885-3177    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

Lipid peroxidation, which may be involved in the pathogenesis of acute pancreatitis, is usually assessed in vitro or indirectly using antioxidants or free radical scavengers. We assessed lipid peroxidation in an in vivo model by measuring ethane exhalation in two models of acute pancreatitis. Edematous acute pancreatitis was induced by a supramaximal intraperitoneal injection of cerulein. Necrotizing acute pancreatitis was induced by retrograde infusion of sodium taurocholate into the pancreaticobiliary duct. Rats were placed in closed chambers and ethane exhalation was measured in aliquots. Ethane exhalation was significantly increased (p< 0.002) in cerulein (n= 12)- but not in taurocholate (n= 6)-induced pancreatitis compared to controls (n= 12 and 6, respectively). Our results suggest that free radicals may play a role in the pathogenesis of edematous pancreatitis but do not play an important role in the progression to necrotizing pancreatitis.

ISSN:0885-3177    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

The important role of oxygen radicals in acute experimental pancreatitis was demonstrated by study of the changes in the antioxidant system in the blood, liver, kidney, and pancreas of rats after the administration of a large quantity of L-arginine (L-Arg). The changes in lipid peroxidation and in reduced and oxidized glutathione were followed, as well as the activities of peroxide-decomposing enzymes (glutathione peroxidase and catalase) and H2O2-producing superoxide dismutases. The results demonstrated that “oxidative stress” develops and acute pancreatitis appears rapidly after L-Arg treatment. Oxidative stress symptoms are expressed 24 h after the final treatment. Slow restitution of the studied antioxidant system can be demonstrated as early as after 48 h.

ISSN:0885-3177    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

Glutamate and related molecules are the major excitatory neurotransmitters in the central nervous system, and their receptors have been localized therein. Little is, however, known about them in the peripheral nervous system. The present study investigated the localization of glutamate receptor subunits of the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA) type (GluR1, GluR2–3, and GluR4) in the pancreas of newborn guinea pigs. With a double-labeling method of immunofluorescence and immuno-tetrahydrochloride reaction, GluR1 and GluR4 immunoreactivities were localized mostly in the insulin-secreting cells in the central mass of the islet, and GluR2–3 immunoreactivity in the peripheral rim of the islet, which consists mainly of non-insulin-secreting islet cells. With a double-labeling method employing immuno-fluorescence and NADPH-diaphorase (NADPH-d) histochemistry, GluR2–3 and GluR4 immunoreactivities were localized in most of the NADPH-d-positive pancreatic ganglion cells. None of the NADPH-d-positive ganglion cells showed GluR1 immunoreactivity. In fact, GluR1 immunoreactivity was not detected in any of the pancreatic ganglion cells. The results indicate that glutamate is likely to exert its effects on the pancreas by activating different AMPA receptor subunits located in endocrine cells and intrapancreatic ganglia.

ISSN:0885-3177    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

The role of endothelin and its relationship with nitric oxide (NO) production in ischemia-reperfusion associated with pancreas transplantation has been explored. For this purpose, pancreatic levels of endothelin were evaluated in an experimental model of pancreas transplantation after different periods of cold preservation. The effects of NO synthase inhibition were also evaluated. Results show posttransplantation increases in lipase and endothelin production. The release of lipase and endothelin was only prevented by NG-nitro-L-arginine methyl ester after a short ischemic period. Thus, endothelin synthesis could be a consequence of stimulation with NO in the ischemiareperfusion associated with pancreas transplantation.

ISSN:0885-3177    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

Fibroblast-like cells in the periacinar region may play an important role in periacinar fibrosis. In the present study, we isolated and cultured periacinar fibroblast-like cells (PFCs) derived from human pancreatic acini and examined the characteristics of human PFCs morphologically and immunocytochemically. Immunocytochemical study of human PFCs showed that they were positively stained with antibodies against type I collagen/procollagen, type III collagen/procollagen, fibronectin, prolyl hydroxylase β subunit, type IV collagen, laminin, α-smooth muscle actin, vimentin, and nonmuscle myosin. Electron microscopic study showed that human PFCs contained a number of microfilaments, forming dense bodies in the cytoplasm.These results indicated that human PFCs possess characteristics of myofibroblasts. Expression of α-smooth muscle actin, a marker of the myofibroblast-like phenotype, was increased with time in culture and was enhanced by treatment with transforming growth factor (TGF)-β1. Collagen synthesis in human PFCs was stimulated by TGF-β1 and the proliferation of human PFCs was stimulated by plateletderived growth factor. These findings suggest that PFCs from human pancreas seem to be involved in periacinar fibrosis.

ISSN:0885-3177    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

In two sets of dogs with gastric, duodenal, and jejunal fistulas, we studied the effect of atropine (14 nmol/kg/h) on the pancreatic secretory response to intrajejunal tryptophan (0.12–10.0 mmol/h; given against a secretin background) before (n= 7) and after extrinsic denervation of the Jejunoileum (orthotopical autotransplantation;n= 6). Plasma levels of cholecystokinin were determined by radioimmunoassay. The incremental bicarbonate response to tryptophan was not significantly different between the two sets of dogs. Atropine had no effect on the incremental bicarbonate response to tryptophan. In both sets of dogs, intrajejunal tryptophan caused a dose-dependent increase in pancreatic protein output, which was reduced by atropine. The tryptophan-stimulated levels of plasma cholecystokinin were not significantly altered by denervation and/or atropine. We conclude that in dogs (1) intrajejunal tryptophan stimulates pancreatic bicarbonate and protein secretion via release of hormones, (2) extrinsic denervation of the Jejunoileum does not significantly alter the incremental bicarbonate and protein responses to intrajejunal tryptophan, (3) the cholinergic intrinsic nerves of the Jejunoileum and the hormone cholecystokinin are probably involved in control of the pancreatic protein response to tryptophan, and (4) the release of cholecystokinin by intrajejunal tryptophan does not depend on the extrinsic and intrinsic cholinergic nerves of the Jejunoileum.

ISSN:0885-3177    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

This study extends a recent observation that Otsuka Long-Evans Tokushima Fatty (OLETF) rats show no expression of the cholecystokinin (CCK)-A receptor gene in the pancreas because of a genetic abnormality. We compared the changes in pancreatic regeneration in terms of wet weight and protein and DNA contents after partial pancreatectomy (30% resection) in OLETF and control (Long-Evans Tokushima Otsuka; LETO) rats and examined whether the CCK-B receptor has a role in pancreatic regeneration after pancreatectomy. The pancreatic wet weight increased significantly with age in both OLETF and LETO rats regardless of surgical procedure, but the increase with respect to time was significantly less in OLETF than in LETO rats. The protein and DNA concentrations in the pancreas (mg/g wet tissue) were comparable for both strains after sham operation. However, they were significantly lower than pancreatectomy in OLETF rats compared to those after sham operation, whereas they were comparable in LETO rats regardless of surgical procedure. The ratio of protein content/DNA content (cell size) was significantly lower in OLETF than LETO rats under all conditions. CCK-B receptor gene expression was not enhanced after pancreatectomy. In conclusion, the CCK-A receptor is not an absolute requirement for pancreatic normal growth but is important for pancreatic regeneration.

ISSN:0885-3177    

出版商:OVID    

年代:1997

数据来源: OVID