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1.
Eur J Surg Oncol ; 48(9): 1882-1894, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35599137

RESUMO

The optimal surgical treatment strategy for gastric cancer in older patients needs to be carefully evaluated due to increased vulnerability of older patients. We performed a database search for randomized controlled trials (RCTs) and cohort studies that included patients ≥70 years with potentially resectable stage I-III gastric cancer. Postoperative and survival outcomes were compared between groups undergoing 1) gastrectomy vs conservative treatment (best supportive care or non-operative treatment), 2) minimally invasive (MIG) vs open gastrectomy (OG), or 3) extended vs limited lymphadenectomy. When possible, results were pooled using risk ratios (RR). Thirty-one studies were included. Six retrospective studies compared overall survival (OS) between gastrectomy (N = 2332) and conservative treatment (N = 246). Longer OS was reported in the gastrectomy group in all studies, but study quality was low and meta-analysis was not feasible. Eighteen cohort studies compared MIG (N = 3626) and OG (N = 5193). MIG was associated with fewer complications (pooled RR 0.68, 95% confidence interval 0.54-0.84). OS was not different between the groups. Two RCTs and five cohort studies compared outcomes between extended (N = 709) and limited lymphadenectomy (N = 1323). Complication rates were comparable between the groups. Two cohort studies found longer OS or cancer-specific survival after extended lymphadenectomy. No quality of life (QoL) or functional outcomes were reported. In older patients with gastric cancer, there is low-quality evidence for better OS after gastrectomy vs conservative treatment. Compared to OG, MIG was associated with less postoperative morbidity. The evidence to support extended lymphadenectomy is limited. QoL and functional outcomes should be addressed in future studies.


Assuntos
Laparoscopia , Neoplasias Gástricas , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Gastrectomia/métodos , Humanos , Excisão de Linfonodo/métodos , Estudos Retrospectivos , Neoplasias Gástricas/patologia , Resultado do Tratamento
3.
Breast ; 60: 263-271, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34808438

RESUMO

BACKGROUND: This study aimed to provide insights into the real-world use of palbociclib, dose reductions, and drug effectiveness in (older) patients with advanced breast cancer (BC). PATIENTS AND METHODS: Patients with advanced BC treated with palbociclib from 2017 to 2020 were included. The Kaplan-Meier method was used to calculate time to next treatment (TTNT) and overall survival (OS) for patients with or without dose reductions. These clinical outcomes were also compared in subgroup analyses for older patients (≥70 years) and younger patients (<70 years) and for patients discontinuing palbociclib early (<4 administrations). RESULTS: A total of 598 patients with advanced BC were included, with a median age of 64 years. Palbociclib dose reductions occurred in 33% of all patients. Early discontinuation of palbociclib without dose reductions occurred in 23% of the patients. Patients who required a palbociclib dose reduction were older (median age 67 years vs. 63 years). Patients with dose reductions had a significantly higher TTNT of 16.9 vs. 11.4 months (p < 0.001) and median OS of 29.7 vs. 21.9 months (p = 0.003) compared to patients without dose reductions. The TTNT in older patients was significantly longer (16.9 vs. 11.6 months, p = 0.013) than younger patients, but OS was similar (20.7 vs. 26.7 months, p = 0.051). CONCLUSION: Palbociclib dose reductions occurred in real-world practice similarly to the PALOMA-3 trial. Patients with dose reductions had no poorer outcomes compared to patients not requiring a dose reduction. Older patients treated with palbociclib had more frequent dose reductions, but this did not appear to affect OS.


Assuntos
Neoplasias da Mama , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Redução da Medicação , Feminino , Humanos , Pessoa de Meia-Idade , Piperazinas , Piridinas , Receptor ErbB-2
4.
Eur J Surg Oncol ; 47(10): 2682-2688, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34127326

RESUMO

BACKGROUND: In order to tailor treatment to the individual patient, it is important to take the patients context and preferences into account, especially for older patients. We assessed the quality of information used in the decision-making process in different oncological MDTs and compared this for older (≥70 years) and younger patients. PATIENTS AND METHODS: Cross-sectional observations of oncological MDTs were performed, using an observation tool in a University Hospital. Primary outcome measures were quality of input of information into the discussion for older and younger patients. Secondary outcomes were the contribution of different team members, discussion time for each case and whether or not a treatment decision was formulated. RESULTS: Five-hundred and three cases were observed. The median patient age was 63 year, 32% were ≥70. In both age groups quality of patient-centered information (psychosocial information and patient's view) was poor. There was no difference in quality of information between older and younger patients, only for comorbidities the quality of information for older patients was better. There was no significant difference in the contributions by team members, discussion time (median 3.54 min) or number of decision reached (87.5%). CONCLUSION: For both age groups, we observed a lack of patient-centered information. The only difference between the age groups was for information on comorbidities. There were also no differences in contributions by different team members, case discussion time or number of decisions. Decision-making in the observed oncological MDTs was mostly based on medical technical information.


Assuntos
Tomada de Decisão Clínica , Comunicação Interdisciplinar , Neoplasias/terapia , Equipe de Assistência ao Paciente , Fatores Etários , Idoso , Tomada de Decisão Clínica/métodos , Comorbidade , Estudos Transversais , Feminino , Humanos , Masculino , Prontuários Médicos/normas , Pessoa de Meia-Idade , Variações Dependentes do Observador , Preferência do Paciente , Assistência Centrada no Paciente
5.
Br J Cancer ; 101(1): 149-59, 2009 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-19513073

RESUMO

BACKGROUND: P53, EGFR and HER-2/neu are the most frequently studied molecular biological parameters in epithelial ovarian cancer, but their prognostic impact is still unequivocal. We performed a meta-analysis to more precisely estimate their prognostic significance. METHODS: Published studies that investigated the association between p53, EGFR and HER-2/neu status and survival were identified. Meta-analysis was performed using a DerSimonian-Laird model. Publication bias was investigated using funnel plots and sources of heterogeneity were identified using meta-regression analysis. RESULTS: A total of 62 studies were included for p53, 15 for EGFR and 20 for HER-2/neu. P53, EGFR and HER-2/neu status had a modest effect on overall survival (pooled HR 1.47, 95% CI 1.33-1.61 for p53; HR 1.65, 95% CI 1.25-2.19 for EGFR and HR 1.67, 95% CI 1.34-2.08 for HER-2/neu). Meta-regression analysis for p53 showed that FIGO stage distribution influenced study outcome. For EGFR and HER-2/neu, considerable publication bias was present. CONCLUSIONS: Although p53, EGFR and HER-2/neu status modestly influences survival, these markers are, by themselves, unlikely to be useful as prognostic markers in clinical practice. Our study highlights the need for well-defined, prospective clinical trials and more complete reporting of results of prognostic factor studies.


Assuntos
Biomarcadores Tumorais/biossíntese , Receptores ErbB/biossíntese , Neoplasias Ovarianas/metabolismo , Receptor ErbB-2/biossíntese , Proteína Supressora de Tumor p53/biossíntese , Feminino , Humanos , Neoplasias Ovarianas/enzimologia , Prognóstico , Modelos de Riscos Proporcionais
6.
Br J Cancer ; 99(2): 341-9, 2008 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-18628764

RESUMO

Ovarian cancer is the most frequent cause of death from gynaecological cancer in the Western world. Current prognostic factors do not allow reliable prediction of response to chemotherapy and survival for individual ovarian cancer patients. Epidermal growth factor receptor (EGFR) and HER-2/neu are frequently expressed in ovarian cancer but their prognostic value remains unclear. In this study, we investigated the expression and prognostic value of EGFR, EGFR variant III (EGFRvIII), HER-2/neu and important downstream signalling components in a large series of epithelial ovarian cancer patients. Immunohistochemical staining of EGFR, pEGFR, EGFRvIII, Her-2/neu, PTEN (phosphatase and tensin homologue deleted on chromosome 10), total and phosphorylated AKT (pAKT) and phosphorylated ERK (pERK) was performed in 232 primary tumours using the tissue microarray platform and related to clinicopathological characteristics and survival. In addition, EGFRvIII expression was determined in 45 tumours by RT-PCR. Our results show that negative PTEN immunostaining was associated with stage I/II disease (P=0.006), non-serous tumour type (P=0.042) and in multivariate analysis with a longer progression-free survival (P=0.015). Negative PTEN staining also predicted improved progression-free survival in patients with grade III or undifferentiated serous carcinomas (P=0.011). Positive pAKT staining was associated with advanced-stage disease (P=0.006). Other proteins were expressed only at low levels, and were not associated with any clinicopathological parameter or survival. None of the tumours were positive for EGFRvIII. In conclusion, our results indicate that tumours showing negative PTEN staining could represent a subgroup of ovarian carcinomas with a relatively favourable prognosis.


Assuntos
Receptores ErbB/metabolismo , Neoplasias Ovarianas/enzimologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Intervalo Livre de Doença , Células Epiteliais/patologia , Receptores ErbB/biossíntese , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Feminino , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Proteína Oncogênica v-akt/metabolismo , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/cirurgia , PTEN Fosfo-Hidrolase/metabolismo , Estudos Prospectivos , Receptor ErbB-2/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Resultado do Tratamento
7.
Eur J Cancer ; 43(17): 2495-505, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17949970

RESUMO

Three amino-acid loop extension (TALE) homeobox proteins MEIS and PBX are cofactors for HOX-class homeobox proteins, which control growth and differentiation during embryogenesis and homeostasis. We showed that MEIS and PBX expression are related to cisplatin resistance in ovarian cancer cell lines. Therefore, MEIS1, MEIS2 and PBX expression were investigated immunohistochemically in a tissue microarray (N=232) of ovarian cancers and ovarian surface epithelium (N=15). Results were related to clinicopathologic characteristics and survival. All cancers expressed MEIS1, MEIS2 and PBX in nucleus and cytoplasm. MEIS1 and 2 only stained nuclear in surface epithelium. Nuclear MEIS2 was negatively related to stage, grade and overall survival in univariate analyses. Additionally, MEIS and PBX RNA expression in ovarian surface epithelium and other normal tissues and ovarian cancer versus other tumour types using public array data sets were studied. In ovarian cancer, MEIS1 is highly expressed compared to other cancer types. In conclusion, MEIS and PBX are extensively expressed in ovarian carcinomas and may play a role in ovarian carcinogenesis.


Assuntos
Proteínas de Homeodomínio/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias Ovarianas/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Proteína Meis1 , Neoplasias Ovarianas/mortalidade , Fatores de Transcrição/metabolismo
8.
Br J Cancer ; 95(5): 627-33, 2006 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-16880779

RESUMO

The prognostic impact of p53 immunostaining in a large series of tumours from epithelial ovarian cancer patients in a two-centre study was analysed. The study population (n=476) comprised of a retrospective series of 188 patients (Dutch cohort) and a prospective series of 288 patients (Scottish cohort) enrolled in clinical trials. P53 expression was determined by immunohistochemistry on tissue microarrays. Association with progression-free survival (PFS) and overall survival (OS) was analysed by univariate and multivariate Cox regression analysis. Aberrant p53 overexpression was significantly associated with PFS in the Dutch and Scottish cohorts (P=0.001 and 0.038, respectively), but not with OS in univariate analysis. In multivariate analysis, when the two groups were combined and account taken of clinical factors and country of origin of the cohort, p53 expression was not an independent prognostic predictor of PFS or OS. In this well-powered study with minimal methodological variability, p53 immunostaining is not an independent prognostic marker of clinical outcome in epithelial ovarian cancer. The data demonstrate the importance of methodological standardisation, particularly defining patient characteristics and survival end-point data, if biomarker data from multicentre studies are to be combined.


Assuntos
Genes p53 , Neoplasias Ovarianas/genética , Proteína Supressora de Tumor p53/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Biomarcadores Tumorais , Feminino , Humanos , Pessoa de Meia-Idade , Análise Multivariada , Estadiamento de Neoplasias , Análise de Sequência com Séries de Oligonucleotídeos , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/terapia , Resultado do Tratamento
9.
Drugs ; 51(4): 507-14, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8706591

RESUMO

This article discusses various aspects of cholesterol-lowering therapy using the HMG-CoA reductase inhibitor simvastatin in the light of the large Scandinavian Simvastatin Survival Study (4S). In 4S, patients with proven coronary heart disease (CHD) and plasma total cholesterol > 5.5 mmol/L (212 mg/dl) despite dietary measures received statin therapy or placebo for > or = 5 years. A significant mortality reduction was accomplished in those receiving the statin. Moreover, a significant decrease of nonfatal myocardial infarction and requirement for coronary bypass surgery or angioplasty was demonstrated, which will contribute to the cost-effectiveness of this well tolerated therapy. Plaque stabilisation and improvement of endothelial function are thought to be mediators of this therapeutic success. Responsible drug prescription in the post-4S era may result in the recognition and treatment of more patients with CHD. This is likely to be more beneficial than exhaustive efforts to completely achieve the goals of the most strict guidelines in the individual patient. In patients who carry the highest absolute risk for a recurrent event, aggressive drug therapy may be most justified. Reluctance to initiate lipid lowering drug therapy in patients with proven CHD should now be disputed.


Assuntos
Anticolesterolemiantes/uso terapêutico , Colesterol/sangue , Doença das Coronárias/tratamento farmacológico , Inibidores de Hidroximetilglutaril-CoA Redutases , Lovastatina/análogos & derivados , Anticolesterolemiantes/administração & dosagem , Anticolesterolemiantes/farmacologia , Ensaios Clínicos Controlados como Assunto , Doença das Coronárias/mortalidade , Doença das Coronárias/prevenção & controle , Análise Custo-Benefício , Dieta , Guias como Assunto , Humanos , Hipercolesterolemia/tratamento farmacológico , Hipercolesterolemia/mortalidade , Estilo de Vida , Estudos Longitudinais , Lovastatina/administração & dosagem , Lovastatina/farmacologia , Lovastatina/uso terapêutico , Sinvastatina
10.
J Cardiovasc Pharmacol ; 18(3): 429-36, 1991 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1720843

RESUMO

In this study, the effect of bradykinin on coronary flow in the isolated rat heart was significantly potentiated when cysteine or the sulfhydryl-containing converting enzyme inhibitors captopril and zofenoprilat were administered simultaneously. In contrast, the effect of concomitant administration of enalaprilat only slightly increased the effect of bradykinin on coronary flow. In nitrate-tolerant hearts of rats pretreated with isosorbide dinitrate (15 mg daily), the increase in coronary flow by nitroglycerin and bradykinin was significantly less when compared to control hearts. The effect of captopril was not affected by pretreatment. The involvement of endothelium-derived relaxing factor (EDRF) in the effect of captopril was apparent from experiments with L-arginine, the precursor of EDRF, and L-NMMA, the "false" precursor of EDRF. L-Arginine increased the effect of captopril, whereas L-NMMA showed a competitive antagonism for the effect of captopril on coronary flow in the isolated rat heart. Clinically, the effect of captopril was studied in 10 patients with stable, exercise-induced angina pectoris that had been treated for 3 weeks with slow-release isosorbide dinitrate (20 mg four times daily). At day 7, a baseline exercise test was obtained. Subsequently, patients with chest pain and at least 1-mm ST-segment depression on the ECG during exercise were included. They received on day 14 and 21 either captopril (25 mg) or placebo 1 h before exercise testing in a randomized, double-blind, crossover design. Captopril significantly improved the combined score of maximal ST-segment depression, maximal workload, and time to angina when compared to placebo. No differences in the pressure-rate index at rest and during exercise were seen. These results indicate that the sulfhydryl group of certain angiotensin converting enzyme inhibitors can potentiate their effect on the endogenous nitrovasodilator EDRF. In the clinical situation, this may lead to an improved exercise performance in patients with stable angina pectoris during chronic nitrate treatment, independent of its systemic vascular effects.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/farmacologia , Nitrocompostos/farmacologia , Compostos de Sulfidrila/farmacologia , Vasodilatadores/farmacologia , Idoso , Angina Pectoris/tratamento farmacológico , Animais , Arginina/análogos & derivados , Arginina/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Bradicinina/antagonistas & inibidores , Bradicinina/farmacologia , Captopril/farmacologia , Circulação Coronária/efeitos dos fármacos , Cisteína/farmacologia , Relação Dose-Resposta a Droga , Humanos , Técnicas In Vitro , Dinitrato de Isossorbida/farmacologia , Masculino , Pessoa de Meia-Idade , Óxido Nítrico/fisiologia , Ratos , Ratos Endogâmicos , ômega-N-Metilarginina
11.
Cardiovasc Drugs Ther ; 4(3): 695-703, 1990 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2076380

RESUMO

The effects of oral zofenopril pretreatment were investigated in a chronic closed-chest pig model of ischemia and reperfusion. Pigs (25-35 kg) were pretreated orally with zofenopril (15 mg/day) on the 2 days prior to ischemia, which was evoked by the inflation of a catheter balloon in the left anterior descending coronary artery over 45 minutes. The catheter was then removed and the myocardium was reperfused. After 2 weeks, infarct properties were assessed by signal averaging of the body surface electrocardiogram and the inducibility of malignant ventricular tachyarrhythmias was tested with a programmed electrical stimulation protocol. A significant increase in the pressure-rate product (43 +/- 11%, mean +/- SEM), indicating the oxygen demand of the heart, was prevented by zofenopril (19 +/- 8%, p less than 0.05). Zofenopril reduced the peak efflux of adrenaline (1302 +/- 213 vs. 3201 +/- 760 pg/ml; p less than 0.05), noradrenaline (402 +/- 54 vs. 902 +/- 282 pg/ml; p less than 0.05), and of the adenosine catabolites inosine and hypoxanthine (56 +/- 4 vs. 78 +/- 9, pg/ml; p less than 0.05) in the coronary venous effluent. The efflux of the cytoplasmatic enzyme creatine phosphokinase was not significantly reduced after zofenopril (p = 0.08). No difference in plasma renin levels between the groups were found. After 2 weeks, late potentials were found only in the surviving animals from the untreated group, i.e., the voltage vector magnitude was more reduced, and a prolongation of the QRS duration and of the terminal low-amplitude part of the high-frequency QRS were found.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Inibidores da Enzima Conversora de Angiotensina/farmacologia , Captopril/análogos & derivados , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Administração Oral , Inibidores da Enzima Conversora de Angiotensina/administração & dosagem , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Animais , Captopril/administração & dosagem , Captopril/farmacologia , Captopril/uso terapêutico , Doença das Coronárias/enzimologia , Doença das Coronárias/prevenção & controle , Creatina Quinase/sangue , Estimulação Elétrica , Coração/efeitos dos fármacos , Coração/fisiologia , Frequência Cardíaca/efeitos dos fármacos , Hemodinâmica/efeitos dos fármacos , Masculino , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/prevenção & controle , Traumatismo por Reperfusão Miocárdica/enzimologia , Miocárdio/enzimologia , Miocárdio/metabolismo , Purinas/metabolismo , Renina/sangue , Suínos , Taquicardia/tratamento farmacológico , Taquicardia/prevenção & controle , Fatores de Tempo , Função Ventricular/efeitos dos fármacos , Função Ventricular/fisiologia
12.
J Cardiovasc Pharmacol ; 13(2): 186-91, 1989 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2468944

RESUMO

The effects of angiotensin II (AII) and captopril (C) on the inducibility of ventricular tachyarrhythmias were investigated 14 days after infarction in pigs. In 27 pigs, ischemia was induced by 60-min occlusion of the left coronary artery. Four pigs died of ventricular fibrillation during ischemia, and six others died within 24 h due to pump failure. Of the 17 survivors, eight pigs developed a sustained (greater than 30 s) monomorphic ventricular tachycardia (sVT) after programmed electrical stimulation. In nine noninducible pigs, an AII infusion (0.6 microgram/kg/min) caused inducible sVT in three animals and nonsustained VT in two animals (greater than 10 reentrant beats). In two of the remaining four animals, spontaneous premature ventricular beats appeared during the infusion. In a group of five healthy pigs, the electrophysiological effects of AII were evaluated. Infusion of AII caused a rapid and sustained increase in arterial blood pressure to 161 +/- 6.4% (p less than 0.001). The sinus cycle length decreased to 74 +/- 5.2% (p less than 0.02). The effective refractory period of the right ventricle decreased significantly to 82 +/- 5.5% (p less than 0.05). These results show that modulation of the renin-angiotensin system after myocardial infarction influences the inducibility of malignant ventricular tachyarrhythmias, as shown by the increased inducibility of sustained ventricular tachycardia. This may be related to a decreased ventricular refractoriness. Therefore, it is suggested that C can reduce malignant ventricular tachycardia late after myocardial infarction by preventing the deleterious arrhythmogenic effects of AII.


Assuntos
Angiotensina II/farmacologia , Captopril/farmacologia , Infarto do Miocárdio/tratamento farmacológico , Taquicardia/tratamento farmacológico , Animais , Doença das Coronárias/complicações , Doença das Coronárias/fisiopatologia , Estimulação Elétrica , Eletrofisiologia , Hemodinâmica/efeitos dos fármacos , Masculino , Infarto do Miocárdio/complicações , Suínos , Taquicardia/etiologia
13.
Circulation ; 77(6 Pt 2): I24-9, 1988 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3286044

RESUMO

The effects of captopril and zofenoprilate (the active form of the prodrug zofenopril and also a sulfhydryl-containing angiotension converting-enzyme inhibitor) on coronary flow in the isolated rat heart were compared with the effects of a nonsulfhydryl converting-enzyme inhibitor, ramiprilate (the active form of the prodrug ramipril) and of sulfhydryl-containing compounds with no converting-enzyme inhibiting properties such as glutathione, cysteine, and the (R,S)-isomer of captopril. Drug concentrations of the angiotensin converting-enzyme inhibitors were equipotent in their effect on angiotensin I pressor response. Concentrations of the other compounds were equimolar with respect to the sulfhydryl group. Hearts treated with captopril, its isomer, zofenoprilate, cysteine, and glutathione showed significant increases in coronary flow by 5 min of perfusion. In contrast, ramiprilate treatment resulted in a slower increase in coronary flow that was only significant after 20 min of perfusion. The effect of ramiprilate was associated with a significant increase in 6-keto-prostaglandin (PG) F1 alpha overflow in the coronary effluent compared with that in saline-treated hearts, whereas captopril and glutathione had no significant effect on overflow of the measured cyclooxygenase products 6-keto-PGF1 alpha, thromboxane B2, and PGE2. The effects of captopril, zofenoprilate, and glutathione on coronary flow were dose dependent. These results corroborate the view that ramiprilate enhances coronary flow by affecting prostacyclin synthesis, mediated by an increase of endogenous bradykinin.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Inibidores da Enzima Conversora de Angiotensina/farmacologia , Captopril/farmacologia , Circulação Coronária/efeitos dos fármacos , Animais , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Doença das Coronárias/fisiopatologia , Relação Dose-Resposta a Droga , Eletrocardiografia , Masculino , Perfusão , Ratos , Ratos Endogâmicos , Volume Sistólico/efeitos dos fármacos , Relação Estrutura-Atividade , Compostos de Sulfidrila/farmacologia , Sístole/efeitos dos fármacos
14.
J Cardiovasc Pharmacol ; 9 Suppl 2: S31-6, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-2441198

RESUMO

The effect of captopril (80 micrograms/ml) on coronary flow in the isolated rat heart was compared with the effects of a non-sulfhydryl-converting enzyme inhibitor, ramipril (15 micrograms/ml), and of a sulfhydryl-containing compound with no converting enzyme-inhibiting properties, glutathione (112 micrograms/ml). Drug concentrations were equipotent in their effect on angiotensin I pressor response and equimolar with respect to the sulfhydryl group. Cyclooxygenase products or their stable metabolites (TXB2, 6-keto-PGF1 alpha and PGE2) were measured in the coronary effluent. Furthermore, the effect of mepacrin (1 microM), indomethacin (1 microM), and FPL 55712 (10 microM) on the changes in coronary flow induced by captopril was studied. Both captopril- and glutathione-treated hearts showed a significant increase in coronary flow already after 5 min treatment. After 60 min treatment, coronary flow was further increased to 185 +/- 9% for captopril-treated hearts and to 210 +/- 11% for glutathione-treated hearts when compared to saline treatment. Ramipril treatment resulted in a slower increase in coronary flow, which was significant after 20 min treatment. After 60 min treatment, this increase was 122 +/- 3% when compared to saline-treated hearts. This effect of ramipril was associated with a significant increase in 6-keto-PGF1 alpha overflow when compared to saline-treated hearts. Captopril and glutathione had no significant effect on overflow of the measured cyclooxygenase products. The effect of captopril and glutathione on coronary flow appeared to be dose dependent in an equimolar range. Simultaneous mepacrin treatment diminished the effect of captopril on coronary flow; indomethacin had no effect, and FPL 55712 potentiated the effect of captopril.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Ácidos Araquidônicos/metabolismo , Captopril/farmacologia , Circulação Coronária/efeitos dos fármacos , Compostos de Sulfidrila/farmacologia , Animais , Ácido Araquidônico , Compostos Bicíclicos com Pontes/farmacologia , Cromonas/farmacologia , Glutationa/farmacologia , Técnicas In Vitro , Indometacina/farmacologia , Masculino , Quinacrina/farmacologia , Ramipril , Ratos , Ratos Endogâmicos
15.
J Cardiovasc Pharmacol ; 9 Suppl 2: S37-42, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-2441199

RESUMO

We previously reported concentration-dependent protection of captopril against ischemia-reperfusion injury in the isolated rat heart. In order to study these effects in vivo, we developed a closed-chest pig model. Reversible occlusion of the left coronary artery was achieved with a PTCA catheter during one hour. Captopril (C) i.v. was given in two different concentrations (0.6 mg/kg/10 min + 0.3 mg/kg/2 hr and 6 mg/kg/10 min + 3.0 mg/kg/2 hr) during the experiments to 11 and 10 pigs, respectively, versus 12 controls, who received only saline. Due to malignant ventricular arrhythmias, nine pigs died during ischemia. At the end of the reperfusion period of two hours, eight pigs were alive in each group. In the C-treated pigs, maximum creatine kinase after two hours of reperfusion was significantly lowered to 6,337 +/- 709 U/L in the high dose group versus 8,285 +/- 851 U/L in the low dose group and 9,635 +/- 1,115 U/L in the saline group. A reduction of local inosine overflow in the coronary sinus was seen. Maximum noradrenaline overflow after 5 min reperfusion diminished dose-dependently to 695 +/- 284 and 3,129 +/- 1,728 pg/ml in the C treated groups versus 4,693 +/- 2,277 pg/ml in the saline group. Mean arterial blood pressure and cardiac output decreased significantly during ischemia and reperfusion, but no significant differences occurred between the treated and untreated groups. Reperfusion arrhythmias, mainly accelerated idioventricular rhythm disturbances, were comparable among the three groups. We conclude that in vivo administration of C reduces myocardial damage upon reperfusion after one hour of ischemia in a dose-dependent way.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Captopril/uso terapêutico , Circulação Coronária , Doença das Coronárias/tratamento farmacológico , Miocárdio/patologia , Animais , Arritmias Cardíacas/etiologia , Doença das Coronárias/complicações , Doença das Coronárias/patologia , Doença das Coronárias/fisiopatologia , Relação Dose-Resposta a Droga , Frequência Cardíaca , Hemodinâmica , Masculino , Concentração Osmolar , Suínos
16.
J Mol Cell Cardiol ; 18(12): 1255-66, 1986 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3820317

RESUMO

The effects of the calcium antagonist, diltiazem, on myocardial injury during ischemia and reperfusion were studied both in vitro, in the isolated rat heart, and in vivo, in a closed-chest pig model. In the isolated rat heart, administration of diltiazem before or at the onset of ischemia resulted in a dose-dependent reduction of the incidence and duration of ventricular fibrillation. This reduction was associated with a dose-dependent reduction in overflow of ATP catabolites (adenosine, inosine, hypoxanthine and xanthine). Both changes were significant at concentrations of 3 X 10(-7) M diltiazem and higher. When 3 X 10(-7) M diltiazem was administered upon reperfusion no effect on the incidence of ventricular fibrillation and on ischemia induced total purine overflow was observed. However, the duration of ventricular fibrillation and purine overflow at 5 min after reperfusion were significantly reduced. In the pig experiments all untreated animals (n = 8) showed accelerated idioventricular rhythm (AIVR) upon reperfusion which lasted for 22 +/- 5 min after which sinus rhythm returned. Only two out of five treated animals (450 micrograms/kg/2 h) had an AIVR. Upon reperfusion both groups showed a substantial rise in noradrenaline concentration in the coronary sinus blood, but after 5 min this was significantly less in the treated group. Creatine kinase-kinetics were not altered by diltiazem, but the maximum creatine kinase level was significantly reduced. Within 4 days after the acute experiment 50% of the untreated animals died suddenly, whereas no sudden deaths occurred in the diltiazem group (P less than 0.05). Seven days after the acute experiment, sustained ventricular tachycardia could be induced with programmed electrical stimulation in three out of four surviving untreated pigs. In none of the diltiazem treated pigs was ventricular tachycardia inducible. The results of this study show that the calcium antagonist diltiazem can beneficially influence the events during ischemia and during reperfusion, both in vitro and in vivo; this benefit is associated with a reduction of ATP catabolism, creatine kinase release and noradrenaline overflow. Furthermore, diltiazem reduces electrical instability in the chronic phase of myocardial infarction.


Assuntos
Arritmias Cardíacas/prevenção & controle , Diltiazem/farmacologia , Trifosfato de Adenosina/metabolismo , Animais , Arritmias Cardíacas/fisiopatologia , Doença das Coronárias/tratamento farmacológico , Doença das Coronárias/fisiopatologia , Técnicas In Vitro , Masculino , Norepinefrina/metabolismo , Perfusão , Ratos , Ratos Endogâmicos , Suínos , Fibrilação Ventricular/prevenção & controle
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