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1.
Nat Genet ; 14(2): 141-5, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8841182

RESUMO

Hereditary pancreatitis (HP) is a rare, early-onset genetic disorder characterized by epigastric pain and often more serious complications. We now report that an Arg-His substitution at residue 117 of the cationic trypsinogen gene is associated with the HP phenotype. This mutation was observed in all HP affected individuals and obligate carriers from five kindreds, but not in individuals who married into the families nor in 140 unrelated individuals. X-ray crystal structure analysis, molecular modelling, and protein digest data indicate that the Arg 117 residue is a trypsin-sensitive site. Cleavage at this site is probably part of a fail-safe mechanism by which trypsin, which is activated within the pancreas, may be inactivated; loss of this cleavage site would permit autodigestion resulting in pancreatitis.


Assuntos
Genes/genética , Pancreatite/genética , Mutação Puntual/genética , Tripsinogênio/genética , Arginina/fisiologia , Cromossomos Humanos Par 7 , Análise Mutacional de DNA , Ativação Enzimática , Éxons/genética , Feminino , Heterozigoto , Humanos , Masculino , Modelos Moleculares , Linhagem , Polimorfismo de Fragmento de Restrição , Conformação Proteica , Estrutura Terciária de Proteína , Tripsina/metabolismo , Tripsinogênio/química
2.
J Natl Cancer Inst ; 89(6): 442-6, 1997 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-9091646

RESUMO

BACKGROUND: Hereditary pancreatitis is an autosomal-dominant disease, with a variable expression and an estimated penetrance of 80%. The gene for this disease has recently been mapped to chromosome 7q35, and the defect is believed to be caused by a mutation in the cationic trypsinogen gene. Acute attacks of abdominal pain begin early in life and the disease often progresses to chronic pancreatitis. Although the risk of pancreatic cancer is thought to be increased in more common types of chronic pancreatitis, the frequency of pancreatic cancer in the inherited type of pancreatitis is uncertain. PURPOSE: The aim of this study was to assess the frequency of pancreatic cancer and other tumors in patients with hereditary form of pancreatitis. METHODS: To determine the natural history of hereditary pancreatitis, we invited all members of the American Pancreatic Association and the International Association of Pancreatology to participate in a longitudinal study of this rare form of pancreatitis. The initial criteria for patient eligibility were as follows: early age (< or = 30 years) at onset of symptoms, positive family history, and absence of other causes. From April 1995 through February 1996, 37 physicians from 10 countries contributed medical records of 246 (125 males and 121 females) patients thought to have hereditary pancreatitis as the most likely diagnosis. This group included 218 patients where the diagnosis appeared to be highly probable and 28 additional patients where the diagnosis of hereditary pancreatitis was less certain: 25 patients who had relatively late onset of disease and a positive family history and three patients with onset of disease before age 30 years but with an uncertain family history. We reviewed all causes of death and compared the observed to the expected frequency of cancer in this historical cohort of patients with hereditary pancreatitis. The strength of the association between pancreatitis and pancreatic cancer was estimated by the standardized incidence ratio (SIR), which is the ratio of observed pancreatic cancer cases in the cohort to the expected pancreatic cancers in the background population, adjusted for age, sex, and country. RESULTS: The mean age (+/- standard deviation [SD]) at onset of symptoms of pancreatitis was 13.9 +/- 12.2 years. Compared with an expected number of 0.150, eight pancreatic adenocarcinomas developed (mean age +/- SD at diagnosis of pancreatic cancer: 56.9 +/- 11.2 years) during 8531 person-years of follow-up, yielding an SIR of 53 (95% confidence interval [CI] = 23-105). The frequency of other tumors was not increased: SIR = 0.7 (95% CI = 0.3-1.6). Eight of 20 reported deaths in the cohort were from pancreatic cancer. Thirty members of the cohort have already been tested for the defective hereditary pancreatitis gene: all 30 carry a mutated copy of the trypsinogen gene. The transmission pattern of hereditary pancreatitis was known for 168 of 238 patients without pancreatic cancer and six of eight with pancreatic cancer. Ninety-nine of the 238 patients without pancreatic cancer and six of the patients with pancreatic cancer inherited the disease through the paternal side of the family. The estimated cumulative risk of pancreatic cancer to age 70 years in patients with hereditary pancreatitis approaches 40%. For patients with a paternal inheritance pattern, the cumulative risk of pancreatic cancer is approximately 75%. CONCLUSIONS: Patients with hereditary pancreatitis have a high risk of pancreatic cancer several decades after the initial onset of pancreatitis. A paternal inheritance pattern increases the probability of developing pancreatic cancer.


Assuntos
Neoplasias Pancreáticas/genética , Pancreatite/genética , Adolescente , Adulto , Idade de Início , Criança , Pré-Escolar , Feminino , Humanos , Incidência , Lactente , Estudos Longitudinais , Masculino , Razão de Chances , Risco
3.
Pancreas ; 21(2): 174-80, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10975712

RESUMO

The purpose of this study was to determine if alcohol consumption and endotoxin injection change the rate of apoptosis in the pancreas. Rats were fed a Lieber-DeCarli diet for 14 weeks. At 14 weeks, the animals were injected with lipopolysaccharide (LPS) or saline and killed. The pancreata were resected and snap frozen. Apoptosis was detected by TUNEL assay. Caspase-3 activity, Bcl-2 (protein), and Fas ligand (mRNA) were assayed in pancreas extracts and alpha-amylase in plasma. Alcohol feeding significantly decreased alpha-amylase and caspase-3 activity, and significantly increased Bcl-2. LPS injection increased caspase-3 activity and decreased Bcl-2. Fas ligand mRNA was increased only in alcohol-fed, LPS-injected rats. TUNEL labeling was significantly increased only in alcohol-fed, LPS-injected rats. These data show that (a) long-term alcohol feeding suppresses apoptosis in the pancreas; (b) LPS increases the rate of apoptosis in the pancreas; (c) caspase-3 activity and Bcl-2 expression change in opposite directions; (d) TUNEL positivity and Fas ligand expression are increased, and Bcl-2 is decreased in ethanol-fed + LPS-injected rats. These results suggest that prolonged alcohol consumption may sensitize acinar cells to endotoxin-induced injury and raise the possibility that a similar mechanism may cause pancreatitis in human alcoholics.


Assuntos
Apoptose/efeitos dos fármacos , Etanol/administração & dosagem , Lipopolissacarídeos/administração & dosagem , Pâncreas/citologia , Animais , Caspase 3 , Caspases/análise , Proteína Ligante Fas , Marcação In Situ das Extremidades Cortadas , Masculino , Glicoproteínas de Membrana/genética , Pâncreas/química , Proteínas Proto-Oncogênicas c-bcl-2/análise , RNA Mensageiro/análise , Ratos , Ratos Sprague-Dawley , alfa-Amilases/sangue
4.
Med Clin North Am ; 84(3): 589-95, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10872416

RESUMO

Much has been learned about hereditary pancreatitis. Much still remains to be explained, including the characteristic 20% nonpenetrance, variable expressivity, and factors affecting risk for pancreatic cancer. There is much work to be done.


Assuntos
Ensaios Clínicos como Assunto , Predisposição Genética para Doença/genética , Pancreatite/genética , Antioxidantes/administração & dosagem , Nutrição Enteral , Alimentos Formulados , Terapia Genética , Humanos , Avaliação de Processos e Resultados em Cuidados de Saúde , Pancreatite/prevenção & controle , Pancreatite/terapia , Prognóstico , Fatores de Risco
5.
Surg Clin North Am ; 79(4): 711-22, vii-viii, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10470321

RESUMO

Hereditary pancreatitis is a rare condition characterized by acute and chronic pancreatitis transmitted in an autosomal dominant fashion. There also is an epidemiologic link to pancreatic cancer in some affected families. Failure of a secondary brake mechanism responsible for inactivation of prematurely activated cationic trypsin in acinar cells seems to be the fundamental defect in type I hereditary pancreatitis (R117H cationic trypsin), and also may explain the pathogenesis of type II hereditary pancreatitis (N211 cationic trypsin). The diagnosis is made based on clinical history and, in certain cases, by molecular diagnostic testing for these gene defects. Medical management of acute and chronic hereditary pancreatitis currently does not differ from that of nonhereditary AP. As in nonhereditary pancreatitis, the surgical approach must be tailored to the individual problem, with an understanding that disease restricted to the head of the gland is atypical and that residual acinar tissue continues to drive the disease state. Although diagnosis and management of pancreatic adenocarcinoma are similar in this cohort, the increased age-accumulated risk suggests that thoughtful screening protocols eventually may be clinically and cost-effective.


Assuntos
Cromossomos Humanos Par 7 , Pancreatite/genética , Mutação Puntual , Tripsinogênio/genética , Adenocarcinoma/genética , Feminino , Humanos , Masculino , Neoplasias Pancreáticas/genética , Pancreatite/complicações , Pancreatite/enzimologia , Pancreatite/fisiopatologia
6.
Postgrad Med ; 100(2): 203-4, 207-12, 214, 1996 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8700818

RESUMO

A review of the relevant English-language literature on bowel cleansing before colonoscopy yielded results of randomized trials comparing a variety of regimens, including polyethylene glycol (PEG)-electrolyte lavage, 3-day clear liquid diet with laxatives or prokinetics, and oral sodium phosphate, as well as these regimens combined with agents such as metoclopramide, cisapride, and senna. Balancing the importance of such factors as cleansing effectiveness, safety, ease of completion, side effects, patient tolerance, and cost, the authors recommend four methods: (1) PEG-electrolyte solution (eg, CoLyte, GoLYTELY, NuLytely) in combination with senna (eg, X-Prep), (2) PEG-electrolyte solution alone (either single dose or split dose), (3) oral sodium phosphate (Fleets Phosphosoda) given in split dose, and (4) oral magnesium citrate in combination with rectal pulsed irrigation.


Assuntos
Colonoscopia , Eletrólitos/administração & dosagem , Polietilenoglicóis/administração & dosagem , Administração Oral , Humanos , Intestinos , Fosfatos/administração & dosagem , Fosfatos/efeitos adversos , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Soluções , Irrigação Terapêutica/métodos
8.
Curr Gastroenterol Rep ; 1(2): 134-8, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10980940

RESUMO

The last few years have seen a rapid evolution in the care of acute pancreatitis. Interventions such as endoscopic sphincterotomy with stone extraction and administration of platelet activating factor are effective but must be applied early. Ranson criteria and modified Glasgow score are widely used, but these systems often cannot separate mild versus severe pancreatitits within 24 hours of hospital admission. The Acute Physiology and Chronic Health Evaluation (APACHE II) is a good predictive system for severity of disease at admission. New single agent biologic markers hold some promise. The CT severity index is better than APACHE II for predicting local complications but not as good for predicting mortality and systemic morbidity. Modern care of acute pancreatitis requires the development of a rapid response team model, with early assessment by APACHE II, biologic markers, and, if indicated, the CT Severity Index.


Assuntos
Pancreatite/diagnóstico , APACHE , Doença Aguda , Humanos , Pancreatite/classificação , Pancreatite/etiologia , Prognóstico , Índice de Gravidade de Doença , Tomografia Computadorizada por Raios X
9.
Dig Dis Sci ; 41(7): 1527-9, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8689935

RESUMO

Vertebral osteomyelitis rarely mimics pancreatitis. However, the potential consequences of longstanding unrecognized disease, including neurological impairment and bony deformity, should make it an item in the differential diagnosis of chronic pancreatitis. In the evaluation of our patient, four items were of particular importance: awareness of his previously documented S. aureus bacteremia, a markedly elevated ESR, an abnormal chest radiograph, and the positive bone scan.


Assuntos
Osteomielite/diagnóstico , Pancreatite/diagnóstico , Doenças da Coluna Vertebral/diagnóstico , Dor Abdominal/etiologia , Doença Crônica , Diagnóstico Diferencial , Discite/complicações , Discite/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Infecções Estafilocócicas/complicações , Infecções Estafilocócicas/diagnóstico , Vértebras Torácicas
10.
Am J Gastroenterol ; 91(7): 1384-7, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8678000

RESUMO

OBJECTIVES: Contrast CT is widely used to assess the severity of acute pancreatitis. Recently, studies in rats have shown that the administration of i.v. contrast material worsens the outcome of experimental acute pancreatitis. The aim of the current study was to determine if an effect of the administration of i.v. contrast could be identified in clinical acute pancreatitis. METHODS: Charts from the University of Kentucky Hospital from 1992 with an ICD-9 code of acute pancreatitis were reviewed. APACHE II scores at diagnosis of pancreatitis were calculated for all patients. The duration of clinical pancreatitis was determined from the date of onset of pain to the date of resolution of pain and resumption of oral nutrition. Contrast CT and noncontrast groups were compared using a Mann-Whitney rank sum test. RESULTS: There was no significant difference in the original APACHE II scores between the two groups. The contrast CT group had a mean duration of clinical pancreatitis of 10.8 days versus 6.2 days for the non-CT group (p = 0.004). CONCLUSIONS: This retrospective study supports the conclusions of recent animal studies that suggest that i.v. contrast might worsen or prolong attacks of acute pancreatitis.


Assuntos
Meios de Contraste , Pancreatite/diagnóstico por imagem , Tomografia Computadorizada por Raios X , APACHE , Doença Aguda , Adulto , Meios de Contraste/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pancreatite/terapia , Estudos Retrospectivos , Estatísticas não Paramétricas , Fatores de Tempo , Tomografia Computadorizada por Raios X/estatística & dados numéricos , Resultado do Tratamento
11.
Am J Gastroenterol ; 90(12): 2232-3, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8540525

RESUMO

Dieulafoy's lesions are an unusual cause of gastrointestinal hemorrhage. The overwhelming majority of lesions are found in the upper gastrointestinal tract, particularly along the lesser curvature of the stomach in the region supplied by the left gastric artery. Rectal Dieulafoy's lesions have never before been reported in the pediatric population, and our case represents only the third reported occurrence of a rectal Dieulafoy's lesion in the English medical literature. Successful treatment was administered, i.e., the combination of sclerotherapy followed by thermocoagulation. We therefore recommend that rectal Dieulafoy's lesion be included in the differential diagnosis of children with severe rectal bleeding and that management follow the same principles used to treat upper gastrointestinal tract Dieulafoy's lesions: injection therapy followed by heater probe coagulation.


Assuntos
Hemorragia Gastrointestinal/diagnóstico , Hemorragia Gastrointestinal/terapia , Pré-Escolar , Diagnóstico Diferencial , Eletrocoagulação , Feminino , Humanos , Reto , Escleroterapia
12.
Am J Physiol ; 264(5 Pt 1): G840-7, 1993 May.
Artigo em Inglês | MEDLINE | ID: mdl-8498511

RESUMO

The cholecystokinin (CCK) receptor on the rat pancreatic acinar cell is a guanine nucleotide-binding protein (G protein)-coupled receptor, which was recently demonstrated to be phosphorylated in response to agonist stimulation (Klueppelberg et al., J. Biol. Chem. 266: 17744-17746, 1991). In this work, we establish that this receptor is phosphorylated in response to a variety of homologous and heterologous secretagogues and that these phosphorylation events represent action by more than one protein kinase. One subgroup of kinases includes one or more isotype of protein kinase C (PKC), and is capable of playing a role in homologous and heterologous desensitization. A second subgroup of kinases that acts on the CCK receptor was defined by its resistance to 10 microM staurosporine, which was shown to inhibit all PKC in these cells. The activity of the second group of kinases was observed only in response to occupation of the CCK receptor by high concentrations of native hormone, raising the possibility of a "receptor-specific kinase." Similar to the prototypical kinase, beta-adrenergic receptor kinase (beta-ARK), this activity was inhibited in permeabilized cells by heparin. Furthermore, like this enzyme activity, beta-ARK was shown to be resistant to staurosporine. Based on its action on a G protein-coupled receptor, its activation at high concentrations of native agonist, and its pattern of inhibition, we believe that the staurosporine-insensitive CCK receptor kinase activity represents either beta-ARK or a closely related member of the receptor-specific kinase enzyme family.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico , Isoenzimas/metabolismo , Pâncreas/metabolismo , Proteína Quinase C/metabolismo , Proteínas Quinases/metabolismo , Receptores da Colecistocinina/metabolismo , Alcaloides/farmacologia , Animais , Carbacol/farmacologia , Relação Dose-Resposta a Droga , Técnicas In Vitro , Cinética , Masculino , Pâncreas/citologia , Pâncreas/enzimologia , Fosforilação , Proteína Quinase C/isolamento & purificação , Ratos , Ratos Sprague-Dawley , Receptores da Colecistocinina/isolamento & purificação , Sincalida/farmacologia , Estaurosporina , Acetato de Tetradecanoilforbol/farmacologia , Quinases de Receptores Adrenérgicos beta
13.
Dig Dis Sci ; 45(5): 927-32, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10795756

RESUMO

Recently, there has been a great deal of interest in the role of cytokines in acute pancreatitis. Serum levels of IL-1, IL-6, and TNF-alpha have been demonstrated to be elevated in acute pancreatitis. We hypothesized that cytokines may be produced primarily by pancreatic parenchymal cells. Reasoning that ductal epithelium is the cell type most likely to be exposed to noxious stimuli in common causes of pancreatitis, such as ERCP and passage of a gallstone, we examined the response of well differentiated pancreatic ductal adenocarcinoma cell lines to stimuli known to stimulate cytokine production in other cells. CAPAN-1 and CAPAN-2 cells were incubated with endotoxin or TNF-alpha. The supernatant was assayed for production of IL-1, IL-6, and IL-8 by ELISA. The cells were assayed for activation of the transcription factor NF-kappaB by electrophoretic mobility shift assay. There was no detectable production of IL-1 by either cell line. CAPAN-1 cells had concentration-dependent production of IL-6 and IL-8 in response to both endotoxin and TNF-alpha. CAPAN-2 cells had concentration-dependent production of IL-6 and IL-8 in response to TNF-alpha. They had low level expression of IL-8 that was unaffected by any concentration of LPS, and no detectable production of IL-6 in response to LPS. These findings suggest that pancreatic duct cells may take an active part in the pathogenesis of acute pancreatitis through the production of cytokines.


Assuntos
Citocinas/metabolismo , Pancreatite/imunologia , Células Tumorais Cultivadas/imunologia , Doença Aguda , Adenocarcinoma , Colangiopancreatografia Retrógrada Endoscópica , Colelitíase/imunologia , Epitélio/imunologia , Humanos , Interleucina-1/metabolismo , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Ductos Pancreáticos/imunologia , Neoplasias Pancreáticas , Fatores de Risco , Fator de Necrose Tumoral alfa/metabolismo
14.
Biochem Biophys Res Commun ; 183(2): 396-404, 1992 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-1550549

RESUMO

Pancreatic acinar cells have both high and low affinity receptors for cholecystokinin (CCK), yet their membranes appear to possess only a single class of binding sites. Recently, gallbladder membrane CCK receptors were shown to undergo inter-conversion between two affinity states dependent on G protein coupling. Keys for that observation were the differential binding affinities of CCK and a phenethyl ester analogue of CCK (OPE), with the high affinity state binding CCK with higher affinity than OPE, and the low affinity state binding OPE with higher affinity than CCK. Here, we performed analogous experiments using these ligands and both pancreatic membranes and a solubilized preparation. Both preparations were found to have only single affinity states of this receptor. However, the state on membranes had a higher affinity for CCK than for OPE, and that on the solubilized preparation had a higher affinity for OPE than for CCK. This supports the hypothesis that the ternary complex of ligand-receptor-G protein found in membranes represents the high affinity state of this receptor, while the uncoupled form of this receptor after solubilization represents its low affinity state. The high affinity of OPE for the solubilized receptor can be utilized in a purification strategy to follow receptor-bearing fractions and to provide an efficient and specific affinity-binding step.


Assuntos
Colecistocinina/análogos & derivados , Cromatografia de Afinidade/métodos , Pâncreas/química , Fragmentos de Peptídeos/metabolismo , Receptores da Colecistocinina/isolamento & purificação , Sincalida/análogos & derivados , Animais , Ligação Competitiva , Membrana Celular/metabolismo , Masculino , Ratos , Receptores da Colecistocinina/metabolismo , Sincalida/metabolismo
15.
Gut ; 48(4): 542-7, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11247900

RESUMO

BACKGROUND: Hereditary pancreatitis (HP) is a rare autosomal dominant disorder with variable expression and an overall lifetime penetrance of 80%. We hypothesised that (1) monozygotic twins within similar environments would develop the typical signs of HP at a similar age, and (2) if penetrance were due to modifier genes or environment, all twin pairs would be concordant for expression of HP. AIM: Identify monozygotic twins with HP and determine the penetrance, concordance, and age of onset of symptoms. METHODS: Twins from HP kindreds were identified from the Midwest Multicenter Pancreatic Study group database, referrals, and literature searches. Each twin set was assessed for phenotypic expression, concordance, and difference in age of phenotypic onset of pancreatitis. The difference in onset of symptoms for symptomatic affected non-twin sibling pairs as well as non-twin pairs that were mutation, sex, and age matched were calculated as two comparison groups. RESULTS: Seven of 11 monozygotic pairs identified were suitable for evaluation and four were concordant for pancreatitis. Forty eight affected sibling pairs and 33 pairs of mutation, sex, and age matched (cationic trypsinogen R122H (30 pairs) and N29I (three pairs)) subjects were identified for comparison groups. The median (quartiles Q1, Q3) difference in the age of phenotypic onset in the concordant twins was 1 (0, 2.4) years, 2 (1, 6) for the affected siblings, and 7 (2, 15) years in the comparison control group. Three of the seven sets of twins (43%) were discordant for phenotypic expression of pancreatitis. The overall penetrance in the seven pairs of monozygotic twins was 78.6%. CONCLUSIONS: Genetic and/or environmental factors contribute to expression and age of onset of HP. Nuclear genes or general environmental factors alone cannot explain the 80% penetrance. Determining the mechanism of non-penetrance may help in developing a strategy to prevent the phenotypic expression of pancreatitis in individuals with an underlying genetic predisposition.


Assuntos
Predisposição Genética para Doença/genética , Pancreatite/genética , Penetrância , Gêmeos Monozigóticos/genética , Adolescente , Adulto , Idade de Início , Criança , Pré-Escolar , Doença Crônica , Feminino , Expressão Gênica , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Mutação/genética , Linhagem , Fenótipo , Reação em Cadeia da Polimerase , Estatísticas não Paramétricas
16.
Dig Dis Sci ; 46(12): 2768-72, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11768272

RESUMO

Interleukin (IL) -6 and IL-8 are cytokines that have been shown to play a role in several pancreatic diseases, including acute pancreatitis, chronic pancreatitis, and pancreatic adenocarcinoma. Previously, we have demonstrated that tumor necrosis factor-alpha (TNF-alpha) and gram-negative bacterial lipopolysaccharide stimulate production of IL-6 and IL-8 and activation of the transcription factor NF-kappaB in the well-differentiated pancreatic ductal adenocarcinoma cell lines CAPAN-1 and CAPAN-2. In these studies we have examined the effect of chain-breaking and glutathione-enhancing antioxidants on NF-kappaB activation and production of IL-6 and IL-8 in these cell lines. Generally, suppression of NF-kappaB activation correlated well with inhibition of IL-6 and IL-8 secretion. In the CAPAN-2 cell line, antioxidants inhibited both NF-kappaB activation and IL-6 and IL-8 secretion. In the CAPAN-1 cell line, antioxidants generally failed to suppress both NF-kappaB activation and IL-6 and IL-8 secretion. The single exception was the chain-breaking antioxidant butylated hydroxyanisole (BHA), which markedly inhibited IL-6 and IL-8 secretion, but had no effect on NF-kappaB activation. These findings may have implications for the treatment of acute and chronic pancreatitis and pancreatic cancer.


Assuntos
Adenocarcinoma/metabolismo , Antioxidantes/farmacologia , Interleucina-6/metabolismo , Interleucina-8/metabolismo , NF-kappa B/metabolismo , Neoplasias Pancreáticas/metabolismo , Hidroxianisol Butilado/farmacologia , Ensaio de Desvio de Mobilidade Eletroforética , Ensaio de Imunoadsorção Enzimática , Humanos , Células Tumorais Cultivadas
17.
J Biol Chem ; 266(4): 2403-8, 1991 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-1989991

RESUMO

The present study was undertaken to determine if the cholecystokinin (CCK) receptor may be phosphorylated, and to gain insight into its regulation. For this, the ATP pool of rat pancreatic acini was prelabeled with 32P, and the cells were stimulated with various secretagogues. CCK receptors from treated cells were enriched by sequential fractionation to produce plasmalemma, and subsequent solubilization and lectin-affinity chromatography. This protocol detected a phosphorylated Mr = 85,000-95,000 plasma membrane glycoprotein with features similar to the CCK receptor. Phosphorylation of this protein occurred rapidly (less than 2 min) and in a concentration-dependent manner in response to CCK, and was inhibited by the CCK receptor antagonist L-364,718. Further evidence that this represented the CCK receptor included comigration of phosphorylated and CCK radioligand affinity-labeled proteins on sodium dodecyl sulfate-polyacrylamide gels, both in native forms and after endoglycosidase F deglycosylation, and the specific adsorption of the phosphoprotein to a CCK analogue affinity resin. Phosphorylation occurred predominantly on serine residues of the receptor protein. Phosphorylation of this protein was also enhanced in response to other secretagogues which, like CCK, stimulate a cascade leading to protein kinase C activation, and in response to direct activation of this enzyme by 12-O-tetradecanoylphorbol 13-acetate. Thus, the pancreatic CCK receptor is phosphorylated in a regulated manner, in response to both homologous and heterologous secretagogues, and to protein kinase C activation.


Assuntos
Pâncreas/metabolismo , Receptores da Colecistocinina/metabolismo , Sincalida/farmacologia , Trifosfato de Adenosina/metabolismo , Animais , Carbacol/farmacologia , Fracionamento Celular , Cromatografia de Afinidade , Cromatografia Líquida de Alta Pressão , Eletroforese em Gel de Poliacrilamida , Ativação Enzimática , Cinética , Masculino , Fosforilação , Proteína Quinase C/metabolismo , Ratos , Ratos Endogâmicos , Solubilidade , Acetato de Tetradecanoilforbol/farmacologia
18.
J Am Intraocul Implant Soc ; 9(4): 473-4, 1983.
Artigo em Inglês | MEDLINE | ID: mdl-6662801

RESUMO

A case of a posteriorly dislocated anterior chamber intraocular lens (IOL) is reported.


Assuntos
Lentes Intraoculares/efeitos adversos , Idoso , Câmara Anterior , Falha de Equipamento , Feminino , Humanos , Atrofia Óptica/complicações , Corpo Vítreo
19.
Am J Physiol ; 266(4 Pt 1): C904-10, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8178963

RESUMO

The phosphorylation of one receptor that occurs as a result of the stimulation of a different receptor on a cell is a common mechanism for heterologous regulation or "cross-talk," which has been implicated in desensitization. In this work, we focus on the mechanisms of phosphorylation of the rat pancreatic acinar cell cholecystokinin (CCK) receptor that occur upon stimulation of this cell by various agonists. Phosphorylation was allowed to occur in dispersed intact acinar cells in response to the experimental manipulation, and the phosphoreceptor was subsequently purified and quantified as an indication of response. Agonists such as vasoactive intestinal polypeptide and secretin, which act via activation of adenylate cyclase, had no effect on CCK receptor phosphorylation, whereas carbamylcholine and bombesin stimulated increased phosphorylation of the CCK receptor. Because these agents would be expected to activate protein kinase C (PKC) as well as a number of calcium-sensitive kinases and phosphatases, these activities were further dissociated by using more direct activators and inhibitors acting intracellularly. Manipulation of calcium independent of PKC by using a calcium ionophore, inhibition of calcium/calmodulin-dependent kinase II, and inhibition of calcium-dependent protein phosphatase type 2B had no effect on the state of CCK receptor phosphorylation.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Receptores da Colecistocinina/metabolismo , Adenilil Ciclases/metabolismo , Animais , Cálcio/metabolismo , Masculino , Fosfoproteínas Fosfatases/metabolismo , Fosforilação , Proteína Quinase C/metabolismo , Ratos , Ratos Sprague-Dawley , Estimulação Química , Fosfolipases Tipo C/metabolismo
20.
J Biol Chem ; 268(16): 12136-42, 1993 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-8389371

RESUMO

Phosphorylation of cell surface receptors regulates the physiological response to many hormones and neurotransmitters. We have demonstrated that the receptor for cholecystokinin (CCK), the major secretagogue for the exocrine pancreas, is phosphorylated on serines in response to CCK (Klueppelberg, U.G., Gates, L.K., Gorelick, F.S., and Miller, L.J. (1991) J. Biol. Chem. 266, 2403-2408). Receptor phosphorylation was transient, even in the continued presence of agonist, and suggested a role for pancreatic protein phosphatases (PP) in regulating receptor phosphorylation in the intact cell. Treatment of acinar cells with okadaic acid increased the extent and duration of receptor phosphorylation induced by CCK. Receptor phosphorylated in the intact cell in response to CCK was used as substrate to analyze protein phosphatases in pancreatic acinar cell extracts. The predominant CCK receptor phosphatase activity was found in the cytosol and was potently inhibited by okadaic acid (IC50 = 0.2 nM). This phosphatase activity was unaffected by inhibitor-2, Ca2+, or Mg2+, suggesting that the major receptor phosphatase was PP-2A. Stimulation of cells with CCK resulted in a 3-fold increase in protein phosphatase activity toward the CCK receptor, at the same time that phosphorylase a phosphatase activity was unchanged. This increase in receptor phosphatase activity was reflected only in the cytosol, with the particulate activity unchanged. Consistent with this subcellular localization, the hormone-regulated receptor phosphatase activity was PP-2A, with chromatographic separation demonstrating activity in both PP-2A1 and PP-2A2 forms. These data suggest that CCK coordinates the activity of both protein kinases and phosphatases acting on the CCK receptor to control the extent and duration of receptor phosphorylation in the pancreatic acinar cell.


Assuntos
Pâncreas/metabolismo , Fosfoproteínas Fosfatases/metabolismo , Fosforilase Fosfatase/metabolismo , Receptores da Colecistocinina/metabolismo , Animais , Cromatografia Líquida , Citosol/enzimologia , Éteres Cíclicos/farmacologia , Técnicas In Vitro , Cinética , Masculino , Ácido Okadáico , Pâncreas/citologia , Fosfoproteínas Fosfatases/antagonistas & inibidores , Fosfoproteínas Fosfatases/isolamento & purificação , Fosforilação , Ratos , Ratos Sprague-Dawley , Frações Subcelulares/enzimologia
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