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1.
Gut ; 52(3): 334-9, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12584212

RESUMO

BACKGROUND: In recent years, there has been an increasing number of cases of early gastric cancer (T1, NX) with intramucosal invasion, which are untreatable by surgical or endoscopic mucosal resection (EMR) because of their high risk. Currently, no adequate treatment is available for such patients. AIM: The main objective of this study was to evaluate whether argon plasma coagulation (APC) is an effective and safe modality for treating early gastric cancer untreatable by surgical resection or EMR. METHODS: The study group comprised 20 men and seven women diagnosed with gastric cancer with intramucosal invasion who were considered poor candidates for surgical resection or EMR due to risk factors such as severe cardiac failure or thrombocytopenia. Irradiation conditions for APC treatment were determined using swine gastric mucosa. We used an argon gas flow of 2 l/min at a power setting of 60 W and a maximum irradiation time of 15 s/cm(2). The follow up period of the 27 patients ranged from 18 to 49 months (median 30 months). RESULTS: All lesions were irradiated easily, including areas anatomically difficult for EMR such as the gastric cardia or the posterior wall of the upper gastric body. In 26 of 27 patients (96%) there was no evidence of recurrence during the follow up period (median 30 months). One patient showed recurrence six months after the treatment but was successfully retreated. No serious complications were found in any of the 27 patients but three patients (11%) experienced a feeling of abdominal fullness. INTERPRETATION: APC is a safe and effective modality for treatment of early gastric cancer with intramucosal invasion untreatable by surgical resection or EMR. However, further observations are necessary to determine the long term prognosis of patients undergoing this treatment.


Assuntos
Adenocarcinoma/cirurgia , Eletrocoagulação/métodos , Neoplasias Gástricas/cirurgia , Adenocarcinoma/patologia , Idoso , Idoso de 80 Anos ou mais , Animais , Feminino , Seguimentos , Mucosa Gástrica/patologia , Gastroscopia , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Neoplasias Gástricas/patologia , Suínos , Resultado do Tratamento
2.
Intern Med ; 40(12): 1222-6, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11813848

RESUMO

A rare case of cardiac malignant fibrous histiocytoma (MFH) is reported. A 55-year-old woman complained of palpitation due to atrial fibrillation. Echocardiography, magnetic resonance imaging, and angiography demonstrated a tumor arising from the posterior wall of the left atrium. At surgery, the tumor was almost entirely resected and histologically defined as MFH. Neither chemotherapy nor irradiation was administered. Echocardiography revealed a local recurrence two months after the surgery and the patient died of advanced cachexy and heart failure 2 years later. The details of this case are presented with a review of the literature.


Assuntos
Neoplasias Cardíacas/diagnóstico , Histiocitoma Fibroso Benigno/diagnóstico , Fatores Etários , Evolução Fatal , Feminino , Neoplasias Cardíacas/patologia , Neoplasias Cardíacas/cirurgia , Histiocitoma Fibroso Benigno/patologia , Histiocitoma Fibroso Benigno/cirurgia , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Prognóstico , Fatores de Risco , Fatores Sexuais
3.
J Toxicol Sci ; 25 Spec No: 103-15, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11349434

RESUMO

The present study was performed to clarify whether toxic effects of the antitumor drug, adriamycin (ADR) on the male genital organ can be adequately detected 2 and 4 weeks after a single intravenous administration in the rat. ADR was intravenously administered once to 10 Crj:CD (SD) male rats/group aged 6 weeks (4-week group) and 8 weeks (2-week group) at doses of 0, 2 and 6 mg/kg. The rats were sacrificed at the age of 10 weeks. For comparison 10 rats/group were killed 2 weeks after a single intravenous administration at the age of 4 weeks (immature group). Saline was administered to control rats. Histopathological examination and a quantitative morphometry were carried out after measurement of testes weights at necropsy. In rats of the 4-week and 2-week groups, mean absolute testicular weight in all groups was significantly decreased. However, changes in mean relative weight were not evident in the 2-week group. Disappearance of seminiferous epithelial cells was observed histopathologically in rats dosed with 2 and 6 mg/kg in the 2-week group. The change was more severe in the 4-week group, when reduction of spermatogenesis and giant cells were also observed at 6 mg/kg. The quantitative morphometry in the 2-week group showed decreases in the numbers of spermatogonia and spermatocytes in stages X and XII at 2 mg/kg, and in the numbers of spermatogonia in all stages and spermatocytes in all stages except stage V at 6 mg/kg. Moreover, the numbers of spermatogonia and spermatocytes in all stages and spermatids in stages II-III and V were decreased with dose related manner in the 4-week group. In contrast, no obvious change in testes weights was apparent in the immature group. However, the numbers of spermatogonia and spermatocytes in all stages were decreased at 6 mg/kg. In conclusion, testicular toxicity of ADR could be detected 2 weeks after a single administration. Susceptibility of the testes of immature rats to ADR might be less than that of older animals.


Assuntos
Antineoplásicos/toxicidade , Doxorrubicina/toxicidade , Testículo/efeitos dos fármacos , Animais , Antineoplásicos/administração & dosagem , Contagem de Células , Relação Dose-Resposta a Droga , Doxorrubicina/administração & dosagem , Testes Hematológicos , Injeções Intravenosas , Masculino , Tamanho do Órgão/efeitos dos fármacos , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Epitélio Seminífero/efeitos dos fármacos , Epitélio Seminífero/patologia , Espermatogênese/efeitos dos fármacos , Testículo/patologia , Testículo/fisiopatologia , Fatores de Tempo , Testes de Toxicidade , Aumento de Peso/efeitos dos fármacos
4.
N Engl J Med ; 339(18): 1277-84, 1998 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-9791143

RESUMO

BACKGROUND: Aberrant crypt foci of the colon are possible precursors of adenoma and cancer, but these lesions have been studied mainly in surgical specimens from patients who already had colon cancer. METHODS: Using magnifying endoscopy, we studied the prevalence, number, size, and dysplastic features of aberrant crypt foci and their distribution according to age in 171 normal subjects, 131 patients with adenoma, and 48 patients with colorectal cancer. We also prospectively examined the prevalence of aberrant crypt foci in 11 subjects (4 normal subjects, 6 with adenoma, and 1 with cancer) before and after the administration of 100 mg of sulindac three times a day for 8 to 12 months and compared the results with those in 9 untreated subjects (4 normal subjects and 5 with adenoma). All 20 subjects had aberrant crypt foci at base line. RESULTS: We identified 3155 aberrant crypt foci, 161 of which were dysplastic; the prevalence and number increased with age. There were significant (P<0.001) correlations between the number of aberrant crypt foci, the presence of dysplastic foci, the size of the foci, and the number of adenomas. After sulindac therapy, the number of foci decreased, disappearing in 7 of 11 subjects. In the untreated control group, the number of foci was unchanged in eight subjects and slightly increased in one (P<0.001 for the difference between the groups). CONCLUSIONS: Aberrant crypt foci, particularly those that are large and have dysplastic features, may be precursors of adenoma and cancer.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Colo/patologia , Neoplasias do Colo/patologia , Lesões Pré-Cancerosas/patologia , Sulindaco/uso terapêutico , Adenoma/genética , Adenoma/patologia , Adenoma/prevenção & controle , Idoso , Estudos de Casos e Controles , Colo/anatomia & histologia , Neoplasias do Colo/complicações , Neoplasias do Colo/genética , Neoplasias do Colo/prevenção & controle , Colonoscopia , Feminino , Genes ras/genética , Cardiopatias/complicações , Cardiopatias/tratamento farmacológico , Humanos , Masculino , Azul de Metileno , Pessoa de Meia-Idade , Osteoartrite/complicações , Osteoartrite/tratamento farmacológico , Mutação Puntual , Lesões Pré-Cancerosas/complicações , Lesões Pré-Cancerosas/tratamento farmacológico , Lesões Pré-Cancerosas/genética , Prevalência , Estudos Prospectivos
5.
Nihon Geka Gakkai Zasshi ; 99(6): 379-84, 1998 Jun.
Artigo em Japonês | MEDLINE | ID: mdl-9695076

RESUMO

Aberrant crypt foci (ACF) are small lesions identifiable in whole-mount preparations of normal-appearing human colonic mucosa with the aid of methyleneblue staining under stereoscopic microscope. Highly frequent mutations of K-ras genes were found, and increased proliferative activities were also observed. Therefore, K-ras gene mutation may have some role in formation of ACF. Using rat experimental model, formation of ACF was shown to be enhanced by cancer promoters (such as secondary bile acids), and to be suppressed by chemopreventive agents (deoxycholic acid and aspirin). Based on these findings, ACF are considered to be precursors of colon cancer. We demonstrated that ACF are the precursors of adenoma-carcinoma sequence. Moreover, we showed that ACF may be suitable biomarkers of chemopreventive agents for colon cancers.


Assuntos
Neoplasias Colorretais/patologia , Neoplasias Colorretais/prevenção & controle , Lesões Pré-Cancerosas/patologia , Lesões Pré-Cancerosas/prevenção & controle , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Biomarcadores Tumorais , Neoplasias Colorretais/genética , Genes fos , Humanos , Lesões Pré-Cancerosas/genética , Ratos
6.
Alcohol Clin Exp Res ; 20(1 Suppl): 33A-35A, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8659685

RESUMO

The Long-Evans Cinnamon (LEC) rat is a mutant strain established from Long-Evans rats that displays spontaneous hepatitis and liver cancer. We previously demonstrated that LEC rats died of acute ethanol intoxication after being fed a liquid diet containing 5% ethanol. Furthermore, we found that both alcohol dehydrogenase (ADH) and aldehyde dehydrogenase activities were remarkably suppressed in the liver of LEC rat, compared with Wistar rats. In the present study, we further investigated ethanol metabolism in the non-ADH pathway and what caused the decrease of liver ADH activity in LEC rats. Blood ethanol concentration 5 hr after intraperitoneal administration of ethanol in LEC rats was higher than in the Wistar rats, indicating that ethanol oxidation was impaired in LEC rats. The expression of liver cytochrome P-450IIE1 in the LEC rat was as much as that in Wistar rats. Regarding decreased ADH activity in the liver of LEC rats, we examined an alternating purine-pyrimidine (CA) repeat-length polymorphism in the first intron of a class I ADH gene that would play a role in altering ADH activity. A polymerase chain reaction method was used to amplify the CA repeat in the first intron of this class I ADH gene, a nine CA repeat insertion and a point mutation were detected in LEC rats. These results suggest that this alternating sequence would modify transcription of the class I ADH gene in LEC rats. Thus, LEC rats have abnormal ethanol metabolism in the ADH pathway.


Assuntos
Álcool Desidrogenase/genética , Intoxicação Alcoólica/genética , Etanol/toxicidade , Íntrons/genética , Mutação Puntual/genética , Polimorfismo de Fragmento de Restrição , Nucleotídeos de Purina/genética , Nucleotídeos de Pirimidina/genética , Animais , Sequência de Bases/genética , Citocromo P-450 CYP2E1 , Sistema Enzimático do Citocromo P-450/genética , Etanol/farmacocinética , Regulação Enzimológica da Expressão Gênica/fisiologia , Neoplasias Hepáticas Experimentais/genética , Masculino , Taxa de Depuração Metabólica/genética , Oxirredutases N-Desmetilantes/genética , Ratos , Ratos Endogâmicos , Ratos Wistar
7.
Alcohol Clin Exp Res ; 20(1 Suppl): 63A-65A, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8659693

RESUMO

Hepatic fibrosis often occurs in alcoholic liver diseases without accompanying tissue necrosis or inflammation. However, the precise mechanism of this fibrosis has not been fully clarified. In the present study, using the hepatoblastoma cell line HepG2 as a model for hepatocytes, we identified a factor that stimulates collagen synthesis of fibroblasts in a conditioned medium of HepG2 cells after treatment with ethanol. Type 1 procollagen peptide (PIC) in a culture of human fibroblast IMR-90 markedly increased after incubation with the conditioned medium of ethanol-treated HepG2 cells. The stimulating activity on the production of PIC by IMR-90 remained after the dialysis and evaporation of the conditioned medium of HepG2 cells, indicating this factor was not as volatile from low molecular substances such as acetaldehyde, acetate, or lactate. The activity of this factor diminished with heat or trypsin treatment. A gel chromatographic analysis disclosed that the molecular weight of this factor was approximately 8000 Da. These results suggest that a polypeptide factor secreted from HepG2 cells by treatment with ethanol stimulates collagen synthesis of fibroblasts.


Assuntos
Carcinoma Hepatocelular/patologia , Transformação Celular Neoplásica/patologia , Colágeno/biossíntese , Cirrose Hepática Alcoólica/patologia , Neoplasias Hepáticas/patologia , Células Tumorais Cultivadas/efeitos dos fármacos , Linhagem Celular , Linhagem Celular Transformada , Fibroblastos , Humanos , Células Tumorais Cultivadas/patologia
8.
J Gastroenterol ; 30(6): 751-7, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8963393

RESUMO

Sera from 14 normal control subjects, 30 patients with alcoholic liver diseases (fatty liver, n = 8; hepatitis, n = 13; liver cirrhosis, n = 9), 7 controls with chronic hepatitis B, and 8 controls with chronic hepatitis C were masured for their concentrations of antibodies against HepG2 membrane protein by a binding assay utilizing 125I-labeled protein A. When the cut-off level was set as the mean value plus 2 SD of normal control subjects, the incidence of positivity was 75%, 69.2%, and 77.8% in patients with alcoholic fatty liver, alcoholic hepatitis, and alcoholic cirrhosis, respectively. Both the mean serum antibody values and the positive incidence were significantly higher in patients with alcoholic liver diseases than in either the normal controls or in the control patients with chronic hepatitis. Sodium dodecylsulfate polyacrylamide gel electrophoresis of 125I-labeled HepG2 membrane protein precipitated with IgG from patients with alcoholic liver diseases revealed an immunoreactive band at a molecular weight of 78,000 daltons (gp78). The antibody activity remained after immunoabsorption by human liver-specific lipoprotein (LSP) but decreased when HepG2 cells were pre-treated with trypsin or neuraminidase. Consequently, gp78 appears to be a glycoprotein distinct from LSP, and is specifically recognized by IgG from patients with alcoholic liver diseases. This assay may provide a new system to measure autoantibody to hepatocytes in alcoholic liver diseases.


Assuntos
Autoanticorpos/imunologia , Hepatopatias Alcoólicas/imunologia , Fígado/imunologia , Proteínas de Membrana/imunologia , Autoanticorpos/análise , Estudos de Casos e Controles , Feminino , Hepatite B/imunologia , Hepatite C/imunologia , Hepatite Crônica/imunologia , Humanos , Imunoglobulina G/análise , Imunoglobulina G/imunologia , Radioisótopos do Iodo , Masculino , Proteínas de Membrana/análise , Pessoa de Meia-Idade , Proteína Estafilocócica A , Células Tumorais Cultivadas
9.
J Gastroenterol ; 29(5): 598-604, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8000508

RESUMO

The effect of ethanol on the expression of asialoglycoprotein receptor protein and its mRNA was studied in a human hepatoma cell line, HepG2. The number of asialoglycoprotein receptors on the cell surface was decreased to 60% of the control level, without a loss in affinity, by incubating the cells with 100 mM ethanol. The decrease in cell surface asialoglycoprotein receptors was paralleled by a decrease in total receptor numbers, including intracellular and surface receptors. The internalization of asialoglycoprotein was also diminished, to 44% of that in control cells. The decreases in cell surface receptors and total receptor numbers were partially restored by 2 mM 4-methylpyrazole, suggesting that ethanol metabolites participated in the diminution of asialoglycoprotein receptor expression. However, the steady-state expression of asialoglycoprotein receptor mRNA was increased in ethanol-treated cells and further augmented by a longer ethanol exposure. These paradoxical results, i.e., the decrease of asialoglycoprotein receptor protein and the increase of its mRNA expression, suggest that the reduction in the asialoglycoprotein receptor protein is a post-transcriptional event and that a possible feedback regulatory mechanism may control asialoglycoprotein receptor gene transcription and/or impair the degradation of its mRNA.


Assuntos
Assialoglicoproteínas/metabolismo , Carcinoma Hepatocelular/metabolismo , Etanol/farmacologia , Neoplasias Hepáticas/metabolismo , RNA Mensageiro/análise , Receptores de Superfície Celular/biossíntese , Receptores de Superfície Celular/genética , Álcool Desidrogenase/antagonistas & inibidores , Receptor de Asialoglicoproteína , Sequência de Bases , Linhagem Celular , Fomepizol , Humanos , Dados de Sequência Molecular , Sondas de Oligonucleotídeos , Pirazóis/farmacologia , Receptores de Superfície Celular/efeitos dos fármacos , Células Tumorais Cultivadas
10.
Jpn J Cancer Res ; 84(3): 219-22, 1993 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8387476

RESUMO

The LEC (Long-Evans cinnamon) rat is a mutant strain displaying hereditary hepatitis and spontaneous hepatocellular carcinoma, and shows abnormal hepatic copper accumulation similar to that occurring in Wilson's disease. We evaluated the iron metabolism of LEC rats compared to LEA (Long-Evans agouti) rats. Hepatic iron and ferritin concentrations were remarkably increased depending on age in LEC rats but not in LEA rats. Increased hepatic iron is normally associated with decreased serum transferrin and total iron binding capacity in hepatic iron overload. In LEC rats, however, both serum transferrin and total iron binding capacity increased with increasing hepatic iron. This increase of serum transferrin and hepatic iron may be an additional important factor contributing to liver injury in LEC rats.


Assuntos
Hepatite Animal/metabolismo , Ferro/metabolismo , Fígado/metabolismo , Fatores Etários , Animais , Western Blotting , Carcinoma Hepatocelular/etiologia , Cobre/metabolismo , Eletroforese em Gel de Poliacrilamida , Ferritinas/análise , Hepatite Animal/complicações , Degeneração Hepatolenticular/complicações , Degeneração Hepatolenticular/metabolismo , Fígado/química , Neoplasias Hepáticas/etiologia , Masculino , Ratos , Ratos Mutantes , Transferrina/análise
11.
Alcohol Alcohol Suppl ; 1B: 105-8, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8003122

RESUMO

The Long-Evans Cinnamon (LEC) rat is a mutant strain established from Long-Evans rats. LEC rats display hereditary hepatitis and spontaneous hepatocellular carcinoma (HCC). We first tried to examine effects of ethanol consumption on the development of HCC, and fed a Lieber's liquid diet containing 5% ethanol to LEC rats. However the rats died within 2 weeks because of acute alcohol intoxication. In LEC rats, the concentration of ethanol and acetaldehyde in blood was significantly higher, and liver alcohol dehydrogenase activity was slightly lower and acetaldehyde dehydrogenase activities were remarkably suppressed compared to those of Wistar rats. These results suggest that LEC rats have hereditary deficiencies of ethanol and acetaldehyde metabolizing enzymes.


Assuntos
Alcoolismo/genética , Transformação Celular Neoplásica/genética , Etanol/farmacocinética , Neoplasias Hepáticas Experimentais/genética , Mutação/genética , Acetaldeído/sangue , Álcool Desidrogenase/genética , Alcoolismo/enzimologia , Alcoolismo/patologia , Aldeído Desidrogenase/genética , Animais , Transformação Celular Neoplásica/patologia , Genótipo , Fígado/enzimologia , Fígado/patologia , Neoplasias Hepáticas Experimentais/enzimologia , Neoplasias Hepáticas Experimentais/patologia , Masculino , Ratos , Ratos Endogâmicos
12.
Jpn J Surg ; 21(6): 621-6, 1991 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1787608

RESUMO

Two different preparations of commercially available suppositories containing Ketoprofen (KP) were administered to 49 patients immediately following anal surgery. The KP was prepared as either fatty suppositories (FS) or gelatin capsulated suppositories (GCS) and surgery was performed under either spinal (n = 37) or local anesthesia (n = 12). Similar results were observed in the kinetics of KP after both FS and GCS administration. The extent of bioavailability of the two dosage forms in the patient groups and control subjects (n = 10) were essentially equal. When the pharmacokinetic parameters of KP were compared between patient groups under spinal and local anesthesia, significant differences were found in the values of the peak level (C max), peak time (T max), and terminal phase half-life (t 1/2). The C max decreased by one-half, while the T max and t 1/2 increased twice and four times, respectively, in patient operated on under spinal anesthesia compared to those operated on under local anesthesia. The absorption rate constant (Ka) following spinal anesthesia was significantly less than that following local anesthesia or that of the healthy subjects (p less than 0.01). A "flip-flop" phenomena could be seen in the time profiles of plasma KP concentration following spinal anesthesia.


Assuntos
Canal Anal/cirurgia , Anestesia Local , Raquianestesia , Hemorroidas/cirurgia , Cetoprofeno/farmacocinética , Administração Retal , Adulto , Idoso , Disponibilidade Biológica , Avaliação de Medicamentos , Humanos , Cetoprofeno/administração & dosagem , Cetoprofeno/uso terapêutico , Pessoa de Meia-Idade , Supositórios
14.
Thromb Res ; 38(6): 611-21, 1985 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-3895562

RESUMO

An enzyme-linked immunosorbent assay (ELISA) for measuring human protein C by using two monoclonal antibodies directed toward the heavy chain of protein C is reported. This assay enabled the determination of protein C in concentrations of 10 to 400 ng/ml in less than 3 hours with a single antigen-antibody reaction. Within-run and between-run coefficients of variation were less than 8%. The mean concentrations of protein C in plasma of 42 normal subjects, 24 patients with liver disease, 27 with DIC, 48 with warfarin therapy and 15 with congenital protein C deficiency, were 4.2, 3.0, 2.3, 2.1 and 1.9 micrograms/ml, respectively. The results obtained with the present ELISA correlated well with those of radioimmunoassay (r = 0.935, n = 81) as well as those of Laurell's Rocket method (r = 0.910, n = 81) by using rabbit anti-human protein C serum. The present method was sensitive and specific for measurement of protein C and also PIVKA-protein C in plasma.


Assuntos
Biomarcadores , Ensaio de Imunoadsorção Enzimática , Glicoproteínas/análise , Técnicas Imunoenzimáticas , Anticorpos Monoclonais/imunologia , Coagulação Intravascular Disseminada/sangue , Feminino , Glicoproteínas/deficiência , Glicoproteínas/imunologia , Humanos , Técnicas Imunológicas , Hepatopatias/sangue , Masculino , Proteína C , Precursores de Proteínas/análise , Protrombina/análise , Varfarina/uso terapêutico
15.
Br J Pharmacol ; 60(4): 529-36, 1977 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-198053

RESUMO

1. Cold storage treatment of the guinea-pig taenia caecum had a greater inhibitory effect on the isoprenaline-induced relaxation than that induced by phenylephrine. Prolonged cold storage (12-14 days) almost abolished the effect of isoprenaline but only reduced the phenylephrine effect. The ED50 of cyclic adenosine 3',5'-monophosphate (cyclic AMP) that elicited muscle relaxation was not altered by the prolonged cold storage. 2. After cold storage treatment, tissue cyclic AMP content was decreased; however, isoprenaline still caused a dose-dependent increase in the cyclic AMP level. The threshold dose of isoprenaline for cyclic AMP accumulation was the same in fresh and cold-stored preparations. 3. In the fresh preparation, the onset of the isoprenaline (10(-6)M)-induced relaxation preceded the increase in tissue cyclic AMP. 4. Isoprenaline, phenylephrine, adrenaline and noradrenaline at doses (ED50) sufficient to induce muscle relaxation did not always increase the cyclic AMP level. 5. Similarly, the responses to papaverine and nitroglycerine were not accompanied by an increase in cyclic AMP. 6. The adenylate cyclase and phosphodiesterase (low and high Km) activities of taenia caecum were not attenuated by the prolonged cold storage. 7. Propranolol inhibited both the isoprenaline-induced relazation and cyclic AMP accumulation; however, the pA2 values were significantly different for the two events. 8. Based on these results, both the relaxation and cyclic AMP accumulation caused by isoprenaline are mediated by activation of beta-adrenoceptors but are independent phenomena.


Assuntos
AMP Cíclico/metabolismo , Isoproterenol/farmacologia , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Fenilefrina/farmacologia , 3',5'-AMP Cíclico Fosfodiesterases/metabolismo , Adenilil Ciclases/metabolismo , Animais , Catecolaminas/farmacologia , Ceco/efeitos dos fármacos , Ceco/metabolismo , Temperatura Baixa , Cobaias , Técnicas In Vitro , Isoproterenol/antagonistas & inibidores , Músculo Liso/metabolismo , Nitroglicerina/farmacologia , Papaverina/farmacologia , Propranolol/farmacologia , Fatores de Tempo
16.
J Cyclic Nucleotide Res ; 3(4): 239-47, 1977 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-199626

RESUMO

Three agents that activate guanylate cyclase, sodium nitroprusside, nitroglycerin and sodium axide, were examined for their effects on cyclic GMP and cyclic AMP accumulation and muscle motility with several tissues. All of these agents, except nitroglycerin with ventricle preparations, increased cyclic GMP levels and did not alter cyclic AMP in incubations of preparations of bovine tracheal smooth muscle, guinea pig tracheal chains, taenia cecum, atria and ventricle, and rat liver and cerebral cortex. Increases in cyclic GMP with these agents occurred with relaxation of smooth muscle preparations and without alteration in the contractility of atrial preparations. These observations support the hypothesis that cyclic GMP accumulation in smooth muscle may be related to relaxation rather than contraction as proposed previously. Relaxation with these agents is not associated with alterations in cyclic AMP levels. Increases in cyclic GMP levels in atrial preparations can also occur without changes in contractile force or rate of contraction.


Assuntos
Azidas/farmacologia , AMP Cíclico/metabolismo , GMP Cíclico/metabolismo , Ferricianetos/farmacologia , Contração Muscular/efeitos dos fármacos , Nitroglicerina/farmacologia , Nitroprussiato/farmacologia , Animais , Bovinos , Feminino , Cobaias , Músculo Liso/efeitos dos fármacos , Músculo Liso/metabolismo , Ratos , Especificidade da Espécie
19.
Arch Int Pharmacodyn Ther ; 225(2): 257-74, 1977 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-403868

RESUMO

Influence of oxygen deficiency and vasodilating drugs on coronary arterial tonus was investigated. In the fibrillating heart, hypoxia initially decreased total coronary resistance, later increased it, and exerted little effect on large coronary arteries. Dilation of helically cut specimens of the small coronary arteries occurred more readily than observed in large arteries in response to N2 bubbling or KCN. In the small arteries, the mitochondrial population was more numerous in cellular units and succinic dehydrogenase activity was greater, suggesting that these vessels are more dependent on aerobic metabolism for the maintenance of integrity. Nitrate vasodilators relaxed selectively the large arteries, while adenosine, prenylamine and carbochromen dilated preferentially the small arteries. Dipyridamole, iproveratril, papaverine and propranolol relaxed both arteries equally; however, except for propranolol, these drugs produced preferential relaxation of the small vessels in the fibrillating hearts.


Assuntos
Angina Pectoris/tratamento farmacológico , Vasos Coronários/fisiologia , Hipóxia/fisiopatologia , Adenosina/farmacologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Vasos Coronários/enzimologia , Vasos Coronários/ultraestrutura , Cianetos/farmacologia , Cães , Técnicas In Vitro , Tono Muscular/efeitos dos fármacos , Nitroglicerina/farmacologia , Papaverina/farmacologia , Cloreto de Potássio/farmacologia , Propilenoglicóis/farmacologia , Succinato Desidrogenase/metabolismo , Resistência Vascular/efeitos dos fármacos , Vasodilatadores
20.
J Pharmacol Exp Ther ; 199(2): 298-309, 1976 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10426

RESUMO

Anthopleurin-A (AP-A), a polypeptide with MW ca. 5500 (53 amino acids), isolated from the sea anemone, Anthopleura xanthogrammica (Brandt), elicited a potent positive inotropic effect but without an accompanying chronotropic effect on the isolated cardiac muscles of rat, rabbit, guinea pig and cat. Similarly in dogs and cats in situ, i.p. injections of AP-A increased the contractile force without effect on heart rate or blood pressure. The cardiotonic potency for AP-A was equivalent to that of isoproterenol but much greater than that for ouabain or glucagon on the isolated cardiac muscle. AP-A increased the contractile force (cardiac output) and decreased atrial pressure in dog heart during pentobarbital-induced failure. This inotropic effect was not inhibited by propranolol pretreatment. The Ca++ requirement to restore the contractile force was less in AP-A-treated than in ouabain or isoproterenol-treated tissues. After AP-A treatment, the cardiac contractility was more resistant to hypoxia and to low or high temperature stress than ouabain-treated or control preparations. AP-A at 5 10(-9) M increased the duration of the action potential, its mean rate of rise and conduction in the guinea-pig atria and ventricles. At the maximum effective concentration, AP-A did not inhibit Na+, K+-activated adenosine triphosphatase, phosphodiesterase (high Km and low Km) and cyclic 3',5'-adenosine monophosphate content of guinea-pig heart. AP-A (5 X 10(-8) to 5 X 10(-7) M) neither contracted nor relaxed the isolated vascular smooth muscle. The results suggest that AP-A may be useful in the clinical management of cardiac failure and as an experimental tool to study the pharmacology and physiology of cardiac muscle.


Assuntos
Cnidários , Contração Miocárdica/efeitos dos fármacos , Peptídeos/farmacologia , Anêmonas-do-Mar , 3',5'-AMP Cíclico Fosfodiesterases/metabolismo , Adenosina Trifosfatases/metabolismo , Animais , Pressão Sanguínea/efeitos dos fármacos , Encéfalo/enzimologia , Cálcio/farmacologia , Gatos , AMP Cíclico/metabolismo , Cães , Feminino , Glucagon/farmacologia , Cobaias , Frequência Cardíaca/efeitos dos fármacos , Técnicas In Vitro , Peptídeos e Proteínas de Sinalização Intercelular , Isoproterenol/farmacologia , Masculino , Potenciais da Membrana/efeitos dos fármacos , Camundongos , Contração Muscular/efeitos dos fármacos , Miocárdio/metabolismo , Ouabaína/farmacologia , Oxigênio/farmacologia , Peptídeos/isolamento & purificação , Peptídeos/toxicidade , Coelhos , Ratos , Temperatura
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