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Query: UMLS:C0030305 (pancreatitis)
 16,014 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This paper is concerned with a hypothesis that disturbance of free radical reactions may lead to abnormality of hemorheological properties in vivo, and so the free radicals generated in vivo may damage certain tissue cells indirectly by reducing the supply of oxygen and nutrients to these cells through slowing the circulation of blood. This hypothesis is based on the following evidence: A. We have found that the whole blood viscosity at low shear rate correlates to the lipid peroxidation in the patients suffering from certain cardio- or cerebrovascular diseases, and in dogs during liver ischemia reperfusion or hemorrhagic pancreatitis. B. Reports have shown that several alterations of hemorheological properties may take place as a result of free radical reactions, such as lipid peroxidation. For instance, lipid peroxidation may lead to decrease of deformability of red cells, increase of aggregation of red cells, formation of liquid thrombin, etc. C. We have demonstrated that some alterations of hemorheological properties involve the role of free radicals in rats suffering from intestinal ischemia/reperfusion. As evidence for this conclusion, superoxide dismutase (SOD) used as a specific scavenger of superoxide anion radical (O2-) can significantly prevent the intestinal ischemia/reperfusion induced changes of lipid peroxidation, red cell aggregation, Cassion's viscosity and whole blood viscosity at low shear rate in rats.
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PMID:A new hypothesis about the relationship between free radical reactions and hemorheological properties in vivo. 818 28

Reperfusion pancreatitis and pancreatic thrombosis are 2 complications of pancreatic transplantation that are associated with both an increased patient morbidity and a decrease in pancreas graft survival rates. These complications are thought to be related to donor factors, procurement and preservation variables, and postimplantation recipient management. We reviewed our experience with 41 consecutive pancreas transplant patients (18 females, 23 males) performed in association with kidney transplants (n = 34), whole (n = 5) and segmental (n = 2). The average cold ischemia time (CIT) was 11.5 hr. Donor and recipient variables were related to two outcomes: (1) postoperative pancreatitis (n = 9) and (2) postoperative pancreatic thrombosis (n = 6). Steroid administration to the donor resulted in significant reduction of postimplantation pancreatitis (P < 0.001). Also, postoperative pancreatitis was significantly less common (P < 0.02) in recipients given calcium channel blockers in the early postoperative period. Pancreatic thrombosis was significantly more common in male recipients (P < 0.04) and was also significantly related to CIT (P < 0.05). These data indicate that proper donor management and pretreatment with high-dose steroids, together with shortening of CIT and postoperative administration of calcium channel blockers, are protective against pancreatic thrombosis and pancreatitis.
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PMID:Risk factors for postimplantation pancreatitis and pancreatic thrombosis in pancreas transplant recipients. 821 56

Early postoperative small bowel obstruction (SBO) is a known complication of intestinal surgery, but its frequency, etiology, and morbidity after abdominal aortic procedures have not been reported. To study this complication, the records of 1475 patients who had an abdominal aortic operation for aneurysmal (n = 818) or occlusive (n = 657) disease on a private surgical service from 1963 to 1990 were reviewed. Forty-four patients (2.9%) developed a postoperative SBO. Small bowel obstruction occurred from 4 to 28 (mean 6) days postoperatively. All patients were treated with nasogastric suction. Eighteen of the 44 (41%) required reoperation from 6 to 30 (mean 14.2) days after the initial aortic procedure. All 18 had lysis of adhesions, and two required small bowel resections. There were no bowel infarctions and no late graft infections. Overall mortality was 5 per cent, and morbidity was 16 per cent. Incidence of pancreatitis in the entire series was 0.5 per cent, and incidence of colonic ischemia in the aneurysm group was 0.9 per cent. We conclude that 1) Early postoperative small bowel obstruction is an unusual complication of aortic surgery but is more frequent than other gastrointestinal complications such as intestinal ischemia and pancreatitis; 2) Management principles are similar to those for early postoperative bowel obstruction following other procedures; 3) Reoperation is required in nearly half of patients, particularly when SBO does not resolve within 2 weeks.
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PMID:Small bowel obstruction after abdominal aortic surgery. 825 41

We investigated microcirculatory changes in sodium taurocholate (ST)-induced pancreatitis. Groups of rats received as tracer either fluorescein isothiocyanate-dextran or acridine orange intravenously. The microcirculation of the exposed pancreas was observed by use of a video camera attached to an epi-illumination microscope. Vessel diameters and plaques of adherent leukocytes were measured with a digital image-analyzing system. In contrast to 0.4 ml of saline, intraductal infusion of ST (4%, 0.4 ml) induced a constriction of interlobular pancreatic arteries of 79 +/- 2% (P < 0.01) within 2 min. This constriction could not be antagonized by the leukotriene antagonist CGP-35949B. The radical scavengers superoxide dismutase (SOD) and N-(2-mercaptopropionyl)glycine (MPG) prevented the arterial constriction. Constriction of pancreatic arteries was accompanied by a decrease of erythrocyte velocity in the pancreatic capillaries. Flux in the head of the pancreas measured by laser-Doppler velocimetry decreased from 300 +/- 69 to 74 +/- 23 perfusion units (P < 0.01) after 446 +/- 159 s. Subsequently an increase of perfusion values was observed indicating reperfusion phenomena. ST induced leukocyte adherence to the walls of interlobular veins forming plaques constituting 39% of the observed venular cross section within 6 min. The leukotriene antagonist, SOD, or MPG prevented leukocyte adherence. Arterial constriction followed by ischemia-reperfusion and leukocyte adherence to venular endothelium during the reperfusion period represented the sequence of microcirculatory changes in ST-induced pancreatitis. The radical scavengers SOD and MPG prevented arterial constriction and leukocyte adherence to venular endothelium, indicating the involvement of free radicals in the pathogenesis of ST-induced pancreatitis in the rat.
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PMID:Arterial constriction, ischemia-reperfusion, and leukocyte adherence in acute pancreatitis. 833 66

Four models of acute pancreatitis have been previously developed that use the ex vivo perfused isolated canine pancreas preparation. The four models include the intraarterial infusion of oleic acid (FFA) that mimics hyperlipemic pancreatitis, partial obstruction of the pancreatic duct with secretin stimulation (POSS) that mimics gallstone pancreatitis, a 2-hour period of ischemia before perfusion (ISCH 2) that mimics shock pancreatitis, and the infusion of cerulein at supramaximal stimulatory doses (CER), which lacks an obvious clinical counterpart. In the FFA, POSS, and ISCH 2 pancreatitis, but not in the CER pancreatitis, toxic oxygen metabolites, generated by the enzyme xanthine oxidase (XO), have been shown to be important mediators in the early pathogenesis. Ordinarily XO primarily occurs as xanthine dehydrogenase (XD) but can be converted to XO, which is the form that generates toxic oxygen metabolites. This conversion of XD to XO may take place either reversibly by way of sulfhydryl group oxidation or irreversibly by means of proteolytic cleavage of XD. This study was undertaken to investigate the mechanism of conversion of XD to XO in the FFA-, POSS-, and ISCH 2-induced pancreatitis models. CER pancreatitis was studied for comparison. After 4 hours of perfusion, pancreatitis was manifest by edema, weight gain, and hyperamylasemia in all four models. Dithiothreitol, a sulfhydryl group protector, ameliorated the weight gain in the FFA (40 +/- 14 gm to 18 +/- 13 gm; p < 0.05), POSS (28 +/- 10 gm to 9 +/- 3 gm; p < 0.05), and ISCH 2 pancreatitis (30 +/- 13 gm to 15 +/- 3 gm; p < 0.05), and ameliorated the hyperamylasemia in the POSS pancreatitis (12,062 +/- 4304 units/dl to 5877 +/- 2659 units/dl; p < 0.05). The CER pancreatitis was not ameliorated with dithiothreitol. A serine protease inhibitor of low molecular weight, phenylmethylsulfonyl fluoride, ameliorated only the CER pancreatitis (weight gain from 28 +/- 10 gm to 17 +/- 10 gm, p < 0.05; amylase activity from 38,116 +/- 6491 units/dl to 23,372 +/- 11,654 units/dl, p < 0.05), and not the FFA, POSS, or ISCH 2 pancreatitis. We conclude that in the three models of pancreatitis (FFA, POSS, and ISCH 2) that are mediated by toxic oxygen metabolites, XD is converted to XO reversibly by way of sulfhydryl group oxidation rather than irreversibly by way of proteolysis. In the CER pancreatitis, where XO does not play a role in the pathogenesis, proteolytic enzymes may be important mediators in the injury.
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PMID:The mechanism of conversion of xanthine dehydrogenase to xanthine oxidase in acute pancreatitis in the canine isolated pancreas preparation. 841 95

Ischemia as a causative factor for acute pancreatitis has been discussed for decades but has only recently gained wider acceptance. Chronic pancreatitis, however, has rarely been attributed to ischemic injury. While experimental evidence is available for the ischemic pathogenesis of acute pancreatitis, no studies have been reported about pancreatic ischemia as a single cause of chronic pancreatitis. Also, the progression from acute to chronic pancreatitis has been a very controversial issue. To address both questions we have injected polystyrene microspheres of 20-microns diameter into the pancreatic branches of the splenic artery of 36 rats. Thirteen more rats were sham operated and injected with saline. The animals were killed at 1, 2, 3, and 9 weeks after operation and macroscopically and histologically examined, and serum alpha-amylase and weight gain were determined. For the pancreas the following parameters were assessed using a score from 0 (no change) to 4 (severe change): atrophy, hemorrhage, edema, fat necrosis, acinar necrosis, polymorphonuclear infiltration, mononuclear infiltration, interstitial fibrosis, and ductal changes. While no difference between control and experiment was observed for serum alpha-amylase, weight gain, edema, and hemorrhage, persistent differences were evident for the parameters characteristic of chronic pancreatitis, most significantly for interstitial fibrosis, ductal changes, mononuclear infiltration, acinar necrosis, and atrophy. No spontaneous deaths occurred. The severity of the lesions remained stationary after the first week. Our work shows for the first time that pancreatic ischemia by microvascular hypoperfusion can cause histopathologic changes characteristic of chronic pancreatitis and that these changes follow acute necrotizing pancreatitis.
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PMID:Does acute pancreatitis progress to chronic pancreatitis? A microvascular pancreatitis model in the rat. 853 54

A porcine pancreatic transplantation model was used to investigate possible protease activation in the pancreatic graft during preservation. After perfusion with Perfadex and cold ischemia for 24 h, but prior to reperfusion, activated carboxypeptidase B was demonstrated in tissue samples from the graft parenchyma with a Western blot technique, indicating that graft pancreatitis may already be initiated during the preservation phase. A higher degree of carboxypeptidase B activation was observed in grafts perfused at a pressure of 130 cm H20 than after perfusion at 70 cm H20. During reperfusion, the fraction of activated carboxypeptidase B gradually declined but was still detectable after 2 h. One group of pigs received aprotinin intravenously during reperfusion, but the protease inhibitor did not influence the degree of carboxypeptidase B activation in the biopsy specimen. Immunoblotting against cationic trypsinogen/trypsin was also performed. When activated trypsin was detectable, it never presented more than a few percent of the total amount of uncomplexed immunoreactive trypsinogen/trypsin.
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PMID:Protease activation in the porcine pancreatic allograft during preservation. 857 79

With the concept that ischemia-reperfusion injury may contribute to the pathogenesis of acute pancreatitis, we have quantitatively analyzed the pancreatic microcirculation of rats during postischemic reperfusion using intravital fluorescence microscopy. Ischemia to the pancreas of Sprague-Dawley rats (N = 7) was induced by clamping the arteriae gastroduodenalis, lienalis, gastrica sinistra, and gastricae breves for 60 min followed by 120 min of reperfusion. Ischemic conditions were verified by measurement of microvascular hemoglobin oxygenation using reflection spectrophotometry (n = 9). Postischemic reperfusion was characterized by a significant (P < 0.05) reduction of functional capillary density to approximately 69% of baseline (no reflow). Reperfusion-induced inflammatory response was reflected by a marked increase (100-fold; P < 0.01) of the number of permanently adherent leukocytes in postcapillary venules (reflow paradox). Postischemic reperfusion was further associated with increased serum lipase activities, and histomorphological analysis revealed alterations, similar as known in acute interstitial pancreatitis, ie, neutrophil infiltration, interstitial edema, and hemorrhagic lesions. We, therefore, conclude that ischemia-reperfusion- associated events, ie, no reflow and reflow paradox, may be considered as trigger mechanisms in the manifestation of distinct types of acute pancreatitis, in particular posttransplant pancreatitis.
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PMID:Ischemia-reperfusion-induced pancreatic microvascular injury. An intravital fluorescence microscopic study in rats. 862 48

The anticardiolipin or antiphospholipid antibody syndrome is characterized by an increased incidence of venous and arterial thromboses. This syndrome may occur in association with systemic lupus erythematosus or independently. Gastroenterological manifestations have included Budd-Chiari syndrome, hepatic infarction, esophageal necrosis with perforation, intestinal ischemia and infarction, pancreatitis, and colonic ulceration. We report a 39-yr-old man with antiphospholipid antibody syndrome complicated by adrenal insufficiency secondary to bilateral adrenal infarction who presented with severe epigastric pain. Endoscopic evaluation disclosed progressive gastric ulceration with necrosis in the distal body. Angiography revealed no vasculitis. Because of intractable pain despite intravenous anticoagulation and narcotic analgesia, the patient was taken to surgery, and an antrectomy with Billroth II gastrojejunostomy was performed. Histological examination revealed widespread vascular occlusive disease involving veins, small arteries, and arterioles present in all layers of the stomach and the perigastric fat consistent with the vasculopathy of the antiphospholipid antibody syndrome. Treatment with high intensity oral anticoagulation and corticosteroids resulted in clinical and endoscopic improvement. This case report extends the gastroenterological manifestations of the antiphospholipid antibody syndrome to include giant gastric ulceration and emphasizes the importance of anticoagulation in treatment.
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PMID:Giant gastric ulceration associated with antiphospholipid antibody syndrome. 912 46

The observation that an elevated level of pancreatic carboxylic ester hydrolase (CEH) in serum is a more sensitive and specific marker of acute pancreatitis than is elevated serum amylase activity prompted us to explore whether these findings could be confirmed in an experimental model and, if so, to find the explanation behind this difference. We therefore developed a model for ischemic pancreatitis in the guinea pig and a sandwich enzyme-linked immunosorbent assay for determination of CEH in this species. There was a strong correlation between duration of ischemia and severity of pancreatic inflammation and between severity of inflammation and serum CEH level. In contrast, serum amylase was elevated only in animals with the most severe grade of inflammation. Amylase was, however, increased in urine in animals with mild inflammation, but the level did not increase with severity of inflammation. Only one of 31 animals had detectable CEH in urine. In animals with intermediate serum CEH levels the serum and biliary concentrations correlated, indicating that CEH may be cleared by the liver. Amylase was detectable in bile only in animals with high serum levels. The results confirm our observations made in previous clinical studies. A likely explanation for differences in serum levels of CEH and amylase is clearance from the circulation at different rates and, at least partly, via different routes, e.g., the liver and kidney, respectively.
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PMID:Carboxylic ester hydrolase and amylase in ischemic pancreatitis in the guinea pig. 874 Apr 7


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