Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0030305 (pancreatitis)
 16,014 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Bile and pancreatic duct ligation (BPDL) in rats does not induce severe acute pancreatitis but only mild inflammation, which is self-limiting and eventually leads to pancreatic atrophy. However, BPDL in opossums induces severe acute necrotizing pancreatitis which uniformly leads to death within 14 days. We compared pancreatic morphologic changes after 24 hr of BPDL in rats and opossums. Pancreatitis histology score and acinar cell ultrastructural changes were evaluated. In both species, BPDL was associated with significant increases in histology score compared to sham controls (5.0 +/- 0.3 vs 1.5 +/- 0.3 in rats, 5.3 +/- 0.4 vs 1.1 +/- 0.1 in opossums; mean +/- SEM, ANOVA, P < 0.05). However, there was no significant difference in histology score between rats and opossums following BPDL; histologic changes, such as white blood cell infiltration, acinar cell vacuolation, and focal acinar cell necrosis, were similar. Acinar cell ultrastructural changes after BPDL in both species included dilated endoplasmic reticulum and autophagic vacuole formation. These findings indicate that the early morphologic changes after BPDL in rats are quite similar to those seen early in the course of BPDL-induced acute necrotizing pancreatitis in opossums. As the rat is a more economical and convenient model to study than the opossum, this study supports the use of the rat model to conduct pilot studies of early events in the development of BPDL-induced acute pancreatitis. This study also suggests the potential for investigating mechanisms that may be present in the rat which protect against progressive and fatal acute necrotizing pancreatitis as observed in opossums after longer periods of BPDL.
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PMID:Ligation-induced acute pancreatitis in rats and opossums: a comparative morphologic study of the early phase. 802 40

We studied morphologic changes in a rat model of acute hemorrhagic pancreatitis in order to investigate the mechanism by which water immersion stress injures the pancreas. Acute hemorrhagic pancreatitis was induced by two intraperitoneal injections of 40 micrograms/kg body weight of caerulein at 1-h intervals under water immersion stress for 5 h at 23 degrees C. Light microscopy showed interstitial edema with inflammatory cell infiltration, degeneration and necrosis of acinar cells, and bleeding. Electron microscopy showed large autophagic vacuoles, decreased zymogen granules, and dilated rough endoplasmic reticulum in acinar cells. Basolateral exocytosis of large vacuoles and phagocytosis of the degenerated acinar cells were observed. In addition, microvascular damage, including the destruction of the capillary endothelial cells, capillary thrombosis, and the extravasation of blood cells, was seen. In contrast, in a pancreatitis model induced by caerulein injection alone, there was no bleeding, no remarkable vascular change, and no thrombosis. Degeneration and necrosis of acinar cells were less severe. In the pancreas under stress alone, microvascular damage and degeneration of acinar cells were observed. These findings demonstrate that stress injures the pancreas and worsens the pancreatitis by causing microcirculatory disturbances, such as vascular damage, thrombosis, increased vascular permeability, and bleeding. These results suggest that chemical mediators, such as free radicals and platelet-activating factor (PAF), which are produced by vascular damage and thrombosis, may accelerate the activation of zymogen proteases in acinar cells in caerulein-induced pancreatitis, leading to hemorrhagic pancreatitis.
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PMID:Ultrastructural study of the effects of stress on the pancreas in rats. 819 Jul 27

Balb/c weanling mice were intraperitoneally inoculated with a myocarditic variant of coxsackievirus B3, with the aim of characterizing more thoroughly the features of virus-induced cell injury in pancreas and heart, as well as to compare ultrastructural alterations with histological and virological findings. During the first week post-infection (pi), all animals developed acinar pancreatitis, followed by focal myocarditis. At electron microscopy, acinar cells showed patent distortion, including marked loss of organelles and zymogen granules, together with gross dilatation of rough endoplasmic reticulum. Cardiac cells presented severe cytoskeletal changes, as myofibrillar collapse with a haphazard arrangement, concomitant with a decrease in myofibril number; besides, irregular pattern of nuclear chromatin and increased presence of swollen mitochondria were often observed. As the few initially detected lymphocytes tended to disappear in necrotic foci, there was an increase in fibroblast number concurrent with progressive scarring. Ultrastructural changes in both pancreas and heart correlated with local viral replication, suggesting that cell damage is attributable to direct viral action.
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PMID:Ultrastructural study of cell injury induced by coxsackievirus B3 in pancreatic and cardiac tissues. 820 11

To evaluate the therapeutic effects and mechanisms of tetramethylpyrazine (TMP), a Chinese herbal medicine, on the lung injury in bile-induced acute haemorrhagic necrotizing pancreatitis (AHNP) in the SD rats, the rats were randomly divided into three groups: sham-operative, untreated and TMP treated. AHNP model were induced by ligation with 5% taurocholate. The changes of lung index, serum lipid peroxide (LPO), TXB2, 6-keto-PGF1 alpha, and lung pathology at light and electron microscope were all investigated at 1, 6, 12 hours after induction of AHNP model. Survival rate of AHNP in rats were recorded also. Results of the study showed that in untreated group, the time-related progressive pancreatic haemorrhage and necrosis, accompanied by pancreatitis-associated lung injury, such as pronounced pulmonary congestion, alveolar and interstitial edema, polymorphonuclear granulocytes infiltration, transparent membrane formation, the density of layer body in type II endothelial cells decreasing, with some vacuole formation, mitochondria, endoplasmic reticulum swollen, basal membrane of endothelial cells rupture were observed. The level of LPO elevated at 1 hour after induction of AHNP and peaked at 12 hours. TXB2 and 6-keto-PGF1 alpha was increased. Using TMP treatment, survival rate increased, and lung at light and electron microscope were much improved and lung index, value of LPO, TXB2 decreased significantly, 6-keto-PGF1 alpha increased slightly, the ratio of TXB2/6-keto-PGF1 alpha was stabilized. It was suggested that TMP has definite therapeutic effects on AHNP-related lung injury in rats, and exerted by scavenging oxygen free radical, inhibiting synthesis of TXA2, augmenting production of PGI2 and maintaining balance between TXA2 and PGI2.
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PMID:[Therapeutic effects and mechanisms of tetramethylpyrazine on lung injury in acute haemorrhagic necrotizing pancreatitis in rats]. 831 99

The biological significance and function of pancreatitis-associated protein (PAP), identified in 1984 as a new secretory protein appearing during pancreatitis, remain to be elucidated. The purpose of this study was to evaluate the presence of PAP in pancreatic tissue upon its exposure to chlorophenylalanine methyl ester (CPME), a drug known to disrupt the regulated secretory pathway of acinar cells, an experimental condition that differs from acute pancreatitis. Pancreatic tissues were processed either for immunocytochemistry or for Northern blot analysis at 17-72 h after a single intraperitoneal injection of CPME in rats. Pancreatic acinar cells displayed endoplasmic reticulum intracisternal crystals consisting of an abnormal aggregation of secretory proteins as well as a sub-population of small and aberrant secretory granules. PAP mRNA was strongly increased at 17-24 h after CPME treatment, and PAP immunoreactivity was detected along the regulated secretory pathway, particularly in the small and aberrant secretory granules at these same time points. Levels of PAP and PAP mRNA decreased gradually, to become undetectable after 72 h. Autoradiographic experiments demonstrated that these small aberrant granules stored preferentially newly synthesized proteins. Our results indicate that the induction of PAP is not exclusive to acute pancreatitis since it appears in pancreatic cells as a response to certain insults and is secreted preferentially through a particular population of small aberrant granules.
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PMID:Presence of pancreatitis-associated protein in pancreatic acinar cells of rats treated with chlorophenylalanine methyl ester. 882 82

Acute necrotising pancreatitis is associated with an unacceptably high mortality for which no satisfactory remedy exists. Emblica officinalis (E.o.) is a plant prescribed in Ayurveda, the Indian traditional system of medicine, for pancreas-related disorders. This study was carried out to evaluate the protective effect of E.o. against acute necrotising pancreatitis in dogs. Pancreatitis was induced by injecting a mixture of trypsin, bile and blood into the duodenal opening of the pancreatic duct. Twenty eight dogs were divided into 4 groups (n = 6-8 each): GpI--control, GpII--acute pancreatitis, GpIII--sham-operated, GpIV--pretreatment with 28 mg E.o./kg/day for 15 days before inducing pancreatitis. Serum amylase increased from 541.99 +/- 129.13 IU/ml to 1592.63 +/- 327.83 IU (p <0.02) 2 hrs after the induction of pancreatitis in GpII. The rise in serum amylase in both GpIII and GpIV was not significant. On light microscopic examination, acinar cell damage was less and the total inflammatory score was significantly lower in the E.o. treated group as compared to GpII. Electron microscopy confirmed this and showed an increased amount of smooth endoplasmic reticulum and small, condensed granules embedded in a vacuole. More studies are needed to explore the clinical potential of E.o. and its mechanism of action.
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PMID:Emblica officinalis: a novel therapy for acute pancreatitis--an experimental study. 885 50

Protease inhibitors may have a beneficial effect in acute pancreatitis. The effects of E3123, a new low molecular weight protease inhibitor, on the ultrastructure of isolated pancreatic acini were examined using transmission electron microscopy. Acini supramaximally stimulated with cerulein (10(-8) M) formed large cytoplasmic vacuoles similar to those generated in the cerulein-induced in vivo model of pancreatitis. Pretreatment of isolated acini with E3123 significantly reduced the size and number of vacuoles associated with cerulein treatment. The distribution of 3H-E3123 in acinar cells was examined using a pulse-chase protocol and electron microscopic autoradiography. Cellular levels of 3H-E3123 increased about 30-fold in acinar cells treated with cerulein (10(-8) M) compared to unstimulated controls. In cerulein-treated acini examined after a 5-min chase, 47.4% of the autoradiographic grains were associated with the rough endoplasmic reticulum and 13.2% were associated with zymogen granules. After 30 min of incubation, the grains associated with the endoplasmic reticulum decreased to 18.5% but increased to 26.3% over zymogen granules. Thus, E3123 is taken up by the acinar cell and follows a cellular itinerary similar to that of newly synthesized secretory proteins. One potential conclusion from these studies is that the ability of E3123 to reduce the formation of vacuoles in supra-maximally stimulated acini may be due to its inhibition of proteases within the secretory pathway.
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PMID:Distribution of a synthetic protease inhibitor in rat pancreatic acini after supramaximal secretagogue stimulation. 905 86

Despite the fact that alcoholism is one of the major causes of pancreatitis, the pathogenesis of this disorder remains obscure. Factors such as the pattern of ethanol consumption, diet, and genetic predisposition may be contributing factors. The failure to produce alcoholic pancreatitis in experimental animals suggests that experimental provision of ethanol may only increase the predisposition to pancreatitis. To test this possibility, we developed an assay system using the in vitro model of cerulein-induced pancreatitis. In this system, pancreatic lobules were first exposed to a supraphysiologic concentration (10(-6) M) of the cholecystokinin analogue, cerulein, after which homogenates were incubated for up to 6 h. Activation of trypsinogen and chymotrypsinogen was observed only in cerulein-treated preparations. We then investigated the effects of the duration of ethanol feeding on cerulein-induced changes in rat pancreas. The pancreata from rats fed ethanol for 9-12 months were more susceptible to cerulein-induced activation of chymotrypsinogen compared to the pancreata from pair-fed control animals. This susceptibility also paralleled morphologic changes, such as dilatation of endoplasmic reticulum, only in the ethanol-fed group. In contrast, during the early stages (up to 3 months) of ethanol consumption, there was resistance (p < 0.01) to cerulein-induced changes. These results suggest that long-term ethanol consumption increases susceptibility to pancreatitis and raises the possibility that a similar mechanism may operate in human alcoholics.
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PMID:Ethanol consumption and susceptibility of the pancreas to cerulein-induced pancreatitis. 905 87

Pancreatitis complicated with infection often results in the development of multiple organ failure. We investigated the role of altered intracellular calcium as a priming signal for cytokine-induced neutrophil chemoattractant expression in this process. Agents modulating cytosolic Ca2+ were utilized to study the in vivo and in vitro cytokine-induced neutrophil chemoattractant expression for macrophages in rats with cerulein-induced pancreatitis after intraperitoneal administration of lipopolysaccharide as a septic challenge. Pretreatment with the calcium channel blocker verapamil significantly reduced serum cytokine-induced neutrophil chemoattractant concentrations in rats with cerulein-induced pancreatitis after septic challenge. Lipopolysaccharide-stimulated in vitro cytokine-induced neutrophil chemoattractant (CINC) production by peritoneal macrophages was significantly enhanced by pretreatment with thapsigargin (an inhibitor of the endoplasmic reticulum-resident Ca2+-ATPase), but not by A23187 (a calcium-specific ionophore, extracellular Ca2+ influx). Pretreatment with U73122 (a phospholipase C inhibitor) inhibited lipopolysaccharide-stimulated but not basal cytokine-induced neutrophil chemoattractant production, while verapamil (a calcium channel blocker), TMB-8 (an inhibitor of calcium release from endoplasmic reticulum), and W7 (calmodulin antagonist) completely abrogated the chemoattractant production. Altered intracellular calcium, due to Ca2+ efflux from intracellular stores, may be involved in the "priming" of macrophages to release cytokine-induced neutrophil chemoattractant following triggering with lipopolysaccharide during acute cerulein pancreatitis.
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PMID:Intracellular calcium affects neutrophil chemoattractant expression by macrophages in rats with cerulein-induced pancreatitis. 955 45

1. After monitoring the changes associated with necrotizing acute pancreatitis in rats from early stages to 24 h after infusion of 5% sodium taurocholate in the choledocus, we characterized by flow cytometry the zymogen granules that still remained in the pancreas 18 h after sodium taurocholate infusion in order to explore whether alterations in the enzyme content and/or in the composition of the granule membrane could be related to the intracellular mechanisms involved in the development of necrotizing acute pancreatitis. 2. Significant increases in the haematocrit, plasma and peritoneal exudate amylase levels and oedema were observed from the third hour after 5% sodium taurocholate infusion onwards. Additionally, cell alterations such as hypergranulation, dilatation of the endoplasmic reticulum and autophagic vacuoles were found 3 and 6 h after infusion. DNA decrease, degranulation and necrosis were observed from 12 h after sodium taurocholate infusion onwards. 3. Flow cytometric measurements of zymogen granules isolated from rat pancreas 18 h after 5% sodium taurocholate infusion revealed a significant decrease in their internal complexity without major changes in their size. Double staining of granules with Tetragonolobus purpureus lectin, which specifically binds L-fucose and specific anti-trypsinogen or anti-amylase antisera, showed that rats with induced pancreatitis have decreased amounts of L-fucose in the membrane glycoconjugates and lower enzyme content (70% and 30% less for trypsinogen and amylase respectively). 4. A decrease in L-fucose in the membrane together with membrane abnormalities observed by electron microscopy in zymogen granules isolated 18 h after sodium taurocholate infusion indicate an altered synthesis of new granules or lysis of preformed zymogen granules which would favour differential loss of granular enzymes, mainly trypsinogen, which in turn could increase the severity of disease.
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PMID:Changes in both the membrane and the enzyme content of individual zymogen granules are associated with sodium taurocholate-induced pancreatitis in rats. 961 64


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