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1.
Biochim Biophys Acta ; 1524(2-3): 203-11, 2000 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-11113569

RESUMO

Induction of endothelial nitric oxide synthase (eNOS) contributes to the mechanism of heart protection against ischemia-reperfusion damage. We analyzed the effects of hypoxia and hyperoxia on eNOS expression in isolated working rat hearts after ischemia-reperfusion damage. Adult male Wistar rats were submitted to chronic hypoxia (2 weeks) and hyperoxia (72 h). The hearts were submitted to 15 min of ischemia and reperfused for 60 min, then we evaluated hemodynamic parameters and creatine phosphokinase (CPK) release. eNOS expression was estimated by RT-PCR; enzyme localization was evaluated by immunohistochemistry and the eNOS protein levels were detected by Western blot. All hemodynamic parameters in hypoxic conditions were better with respect to other groups. The CPK release was lower in hypoxic (P<0.01) than in normoxic and hyperoxic conditions. The eNOS deposition was significantly higher in the hypoxic group versus the normoxic or hyperoxic groups. The eNOS protein and mRNA levels were increased by hypoxia versus both other groups. Chronic hypoxic exposure may decrease injury and increase eNOS protein and mRNA levels in heart subjected to ischemia-reperfusion.


Assuntos
Endotélio Vascular/metabolismo , Coração/fisiopatologia , Isquemia Miocárdica/fisiopatologia , Óxido Nítrico Sintase/metabolismo , Traumatismo por Reperfusão/fisiopatologia , Animais , Western Blotting , Creatina Quinase/análise , Endotélio Vascular/enzimologia , Hemodinâmica , Hiperóxia/fisiopatologia , Hipóxia/fisiopatologia , Imuno-Histoquímica , Masculino , Miocárdio/metabolismo , Miocárdio/patologia , Óxido Nítrico Sintase/biossíntese , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase Tipo III , Técnicas de Cultura de Órgãos , Biossíntese de Proteínas , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transcrição Gênica , Função Ventricular Esquerda
2.
Cardiovasc Res ; 51(2): 283-93, 2001 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-11470468

RESUMO

OBJECTIVE: We tested the hypothesis of beneficial effects of the 3-hydroxy-3-methyl-glutaryl coenzyme A (HMG-CoA)-reductase inhibitor simvastatin in a model of ischemia-reperfusion, and investigated potential mechanisms. METHODS: Isolated working rat hearts were subjected to 15 min global ischemia and 22-180 min reperfusion in the presence or absence of simvastatin (10-100 microM). We evaluated creatinephosphokinase and nitrite levels in coronary effluent, heart weight changes, microvascular permeability (extravasation of fluoresceine-labeled albumin), ultrastructural alterations, and the expression of endothelial (e) and inducible (i) nitric oxide synthase (NOS) (by reverse-transcribed polymerase chain reaction and Western blotting) in the presence or absence of the transcriptional inhibitor actinomycin-D. RESULTS: Simvastatin (25 microM) significantly reduced myocardial damage and vascular hyperpermeability, concomitant with a reduction in endothelial and cardiomyocyte lesions. Protection became less evident at 50 microM and reverted to increased damage at 100 microM. At 25 microM, simvastatin significantly increased eNOS mRNA and protein compared with untreated hearts, probably due to a post-transcriptional regulation since unaltered by animal pretreatment with actinomycin D. Simvastatin also significantly decreased iNOS mRNA and protein, as well as nitrite production after ischemia-reperfusion. The addition of the NOS inhibitor N(pi)-nitro-L-arginine methylester (L-NAME, 30 microM) to 25 microM simvastatin-treated hearts significantly reduced cardioprotection against ischemia-reperfusion. CONCLUSIONS: In this model, in the absence of perfusing granulocytes, the acute administration of a pharmacologically relevant simvastatin concentration reduces ischemia-reperfusion injury and prevents coronary endothelial cell and cardiomyocyte damage by cholesterol-independent, NO-dependent mechanisms.


Assuntos
Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miocárdio/metabolismo , Óxido Nítrico Sintase/antagonistas & inibidores , Sinvastatina/farmacologia , Análise de Variância , Animais , Western Blotting/métodos , Permeabilidade Capilar/efeitos dos fármacos , Creatina Quinase/metabolismo , Inibidores Enzimáticos/farmacologia , Processamento de Imagem Assistida por Computador , Masculino , Miocárdio/ultraestrutura , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase Tipo II , Óxido Nítrico Sintase Tipo III , Nitritos/metabolismo , Tamanho do Órgão/efeitos dos fármacos , Perfusão , RNA Mensageiro/análise , Ratos , Ratos Wistar , Função Ventricular Esquerda/efeitos dos fármacos
3.
Atherosclerosis ; 155(1): 53-9, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11223426

RESUMO

BACKGROUND: the cardiac Renin-Angiotensin system (RAS) plays an important role in the regulation of coronary flow and cardiac function and structure in normal and pathological conditions such as ischemia-reperfusion (I/R) injury. The aim of this study was to investigate the effects of the Angiotensin II type 1 (AT-1) receptor antagonist MK-954 (losartan potassium) on postischemic endothelial dysfunction and NOS mRNA expression (inducible nitric oxide synthase, iNOS; endothelial nitric oxide synthase, eNOS) in isolated working rat hearts. METHODS: isolated working rat hearts were subjected to 15 min global ischemia and 180 min reperfusion. MK-954 was added to perfusion buffer (a modified Krebs-Henseleit solution) at 1 microM concentration. We assessed functional parameters, creatin kinase (CK) release, heart weight changes, microvascular postischemic hyperpermeability (FITC-albumin extravasation) and morphological ultrastructural alterations. eNOS and iNOS mRNA levels were also detected by the means of multiplex RT-PCR technique using glyceraldehyde-3-phosphate dehydrogenase (G3PDH) gene as internal control; results were expressed as densitometric ratio. RESULTS: in Losartan-treated hearts we observed a significant reduction of postischemic contractile dysfunction, CK release and myocardial ultrastructural damage; postischemic FITC-albumin extravasation was significantly reduced respect to controls. Moreover, 1 microM Losartan produced a significant reduction of eNOS/G3PDH respect to untreated hearts submitted to I/R. Regarding iNOS/G3PDH ratio, no significant changes were detected in Losartan-treated hearts compared with controls. CONCLUSIONS: our study revealed that Losartan treatment before ischemia, and during reperfusion, is able to reduce the reperfusion injury of the rat heart by reducing mechanical and microcirculatory dysfunction and necrotic cell death, ameliorating cardiac ultrastructure and endothelial protection, probably inducing eNOS over-expression and reducing post-ischemic hyperpermeability of coronary microcirculation.


Assuntos
Antagonistas de Receptores de Angiotensina , Endotélio Vascular/efeitos dos fármacos , Losartan/farmacologia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Óxido Nítrico Sintase/metabolismo , Animais , Permeabilidade Capilar , Circulação Coronária , Creatina Quinase/metabolismo , Endotélio Vascular/patologia , Técnicas In Vitro , Masculino , Contração Miocárdica/efeitos dos fármacos , Isquemia Miocárdica/patologia , Isquemia Miocárdica/fisiopatologia , Traumatismo por Reperfusão Miocárdica/enzimologia , Traumatismo por Reperfusão Miocárdica/patologia , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Miocárdio/enzimologia , Miocárdio/ultraestrutura , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase Tipo II , Óxido Nítrico Sintase Tipo III , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa
4.
Ann Clin Lab Sci ; 31(2): 179-86, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11337908

RESUMO

Several studies suggest that nitric oxide (NO) production is reduced in diabetes and that the decrease of NO may be related to the pathogenesis of diabetic endothelial damage. NO synthase (NOS) catalyses the conversion of L-arginine to L-citrulline in the presence of oxygen and NADPH-diaphorase (NADPH-d). In this study, we evaluated the expression of endothelial NOS (eNOS) enzyme and its co-enzyme in diabetic rat hearts. Male Wistar rats (n = 20, 4 mo old) and 20 male Bio Breeding Wistar (BB/W) rats of the same age were used; the Wistar rats represent the control non-diabetic rats while the BB/W rats represent the diabetic group. After the hearts were excised, the NADPH-d co-enzyme was visualized by a histochemical method and the endothelial isoform of NOS was localized by immunohistochemistry. In addition, eNOS gene expression was estimated by rt-PCR, and eNOS protein level was detected by Western blot analysis. The eNOS visualization, which involved immunoprecipitation, and the NADPH-d visualization, which involved histochemical staining, were both diminished in endothelial cells of the vascular wall of diabetic hearts, compared to non-diabetic hearts. The eNOS protein level, evaluated by Western blotting, was evident as an intense band in cardiac homogenates of non-diabetic and diabetic rats. The expression of mRNA for eNOS did not differ significantly between the two groups. These findings indicate that, in this rat heart model, diabetes does not influence the overall eNOS protein level or its mRNA level. However, there a diminution in the deposition of eNOS in cardiac endothelial cells of diabetic rats, versus non-diabetic controls, suggesting a relation between eNOS and the loss of vasodilatory response that is observed in diabetes.


Assuntos
Diabetes Mellitus Tipo 1/enzimologia , Miocárdio/enzimologia , Óxido Nítrico Sintase/análise , Óxido Nítrico Sintase/genética , Animais , Western Blotting , Histocitoquímica , Imuno-Histoquímica , Masculino , NADPH Desidrogenase/análise , Óxido Nítrico Sintase Tipo III , RNA Mensageiro/análise , Ratos , Ratos Endogâmicos BB , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa
5.
Respir Med ; 104(10): 1410-6, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20483574

RESUMO

Omalizumab is a humanized murine monoclonal antibody directed toward a portion of the IgE indicated in Europe for the treatment of severe persistent allergic asthma, inadequately controlled despite high-dose of ICS (mean BDP equivalent dose of inhaled corticosteroid 2224.68microg/die) in association with long-acting beta(2) agonists. Our aim was to describe the experience, efficacy and safety in a cohort of Italian patients treated with omalizumab in a real-life clinical setting. One hundred and forty two patients from 13 Italian Centers were observed and analysed. The dosage of omalizumab was established according to the labelling indication, with a median dose of IgE of 297.38IU/ml or kU/l. During the previous year, all patients experienced frequent exacerbations (mean=4.87), emergency visits (mean=4.45) and hospitalisation (mean=1.53). Following treatment with omalizumab, the annual rate of exacerbations, emergency visits and hospitalisation decreased by 79%, 88% and 95%, respectively. The proportion of patients without exacerbation, not needing emergency visits and hospitalization increased by 610%, 154% and 28%, respectively. The response to omalizumab measured with the GETE (global evaluation of treatment effectiveness) scale rated as good to excellent in 77% of patients. Overall, 9.6% (n=9) of the patients experienced one single adverse effect. Only one patient reported a serious adverse event (local reaction at the site of injection) leading to interruption of treatment. The observed reduction of asthma-related events in particularly poorly controlled patients in this Italian real-life setting is consistent with the results of other observational studies.


Assuntos
Antialérgicos/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Asma/tratamento farmacológico , Adolescente , Adulto , Idoso , Anticorpos Anti-Idiotípicos , Anticorpos Monoclonais Humanizados , Asma/fisiopatologia , Relação Dose-Resposta a Droga , Feminino , Volume Expiratório Forçado/efeitos dos fármacos , Volume Expiratório Forçado/fisiologia , Hospitalização/estatística & dados numéricos , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Omalizumab , Índice de Gravidade de Doença , Resultado do Tratamento , Adulto Jovem
10.
Curr Pharm Des ; 15(8): 883-92, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19275652

RESUMO

Progressions in acute cardiac care have improved survival after acute myocardial infarction, but in contraposition with this, there has been an increase in mortality because of heart failure. For this reason congestive heart failure is an increasingly widespread, costly and deadly disease, frequently named as epidemic of the XXI century. Despite advancement in modern treatment, mortality rate in heart failure patients remains high. In these patients more importance was attributed in the management of the left ventricle dysfunction. In fact, the heart failure patients have still a poor prognosis due to the ineluctable progression of contractile dysfunction and ventricular remodeling. The classical management of left ventricle dysfunction includes the pharmacological treatment with beta-blockers, ACE-inhibitors and aldosterone antagonists, and various surgical or electrophysiological interventions. Emerging evidence suggests that myocardium dysfunction is also due to substrate metabolism alterations. In particular, there is evidence that, in the failing heart, shifting metabolism away from a preference for fatty acids towards more carbohydrate oxidation could recover contractile function. Trimetazidine has been shown to improve symptoms and ventricular function and to have a beneficial effect on the inflammatory profile and endothelial function in these patients. Recently, it has been suggested that trimetazidine could also reduce ventricular remodeling, slowing down the progression of pump failure, and improve prognosis. These results suggest that trimetazidine is a useful adjunct to our current armamentarium for the treatment of heart failure patients.


Assuntos
Insuficiência Cardíaca/metabolismo , Trimetazidina/farmacologia , Vasodilatadores/farmacologia , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/fisiopatologia , Humanos , Prognóstico , Medição de Risco , Trimetazidina/uso terapêutico , Vasodilatadores/uso terapêutico , Função Ventricular Esquerda/efeitos dos fármacos , Remodelação Ventricular/efeitos dos fármacos
11.
Heart ; 91(2): 161-5, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15657223

RESUMO

OBJECTIVE: To investigate the long term effects of trimetazidine in patients with dilated ischaemic cardiomyopathy. The effects of trimetazidine on left ventricular function as well as its tolerability profile and potential anti-inflammatory effects were studied. DESIGN: 61 patients were randomly assigned either to receive trimetazidine (20 mg thrice daily) in addition to their conventional treatment or to continue their usual drug treatment for 18 months. Patients were evaluated at baseline and at 6, 12, and 18 months with a clinical examination, echocardiography, and biochemical analysis (C reactive protein). RESULTS: Trimetazidine added to the usual treatment significantly improved the patients' functional status (assessed by New York Heart Association functional class). The functional improvement of trimetazidine treated patients was associated with a significant increase in left ventricular ejection fraction (30 (6)%, 32 (8)%, 38 (7)%, and 37 (6)% v 31 (8)%, 30 (7)%, 28 (6)%, and 26 (9)% in control patients at baseline and at 6, 12, and 18 months, respectively) and with a significant effect on ventricular remodelling. C reactive protein plasma concentrations remained stable throughout the study in patients receiving trimetazidine (2.5 (1.0), 2.7 (2.0), 2.7 (3.0), and 3.0 (2.0) mg/l at baseline and at 6, 12, and 18 months, respectively) but increased significantly in the control group (2.4 (1.0), 3.4 (1.2), 6.0 (4.0), and 7.0 (5.0) mg/l, respectively). No significant adverse event or changes in clinical or biochemical parameters were detected. CONCLUSION: Treatment with trimetazidine added to the usual treatment for up to 18 months was well tolerated and induced a functional improvement in patients with dilated cardiomyopathy. Trimetazidine treatment was associated with a significant improvement of left ventricular function and the remodelling process. Results also suggest that the inflammatory response was limited in patients treated with trimetazidine.


Assuntos
Anti-Inflamatórios/uso terapêutico , Proteína C-Reativa/metabolismo , Cardiomiopatia Dilatada/tratamento farmacológico , Trimetazidina/uso terapêutico , Vasodilatadores/uso terapêutico , Disfunção Ventricular Esquerda/tratamento farmacológico , Idoso , Análise de Variância , Cardiomiopatia Dilatada/sangue , Feminino , Humanos , Assistência de Longa Duração , Masculino , Projetos Piloto , Resultado do Tratamento , Disfunção Ventricular Esquerda/sangue
12.
Allergy ; 56(1): 29-34, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11167349

RESUMO

BACKGROUND: In allergic rhinitis, allergenic stimulation causes the release of various mediators that induce symptoms and the development of chronic inflammation, which, in turn, is caused by cells involved in the late phase of inflammation, such as eosinophils. The eosinophils also cause damage at the mucosal level through the secretion of eosinophil cationic protein and other preformed factors contained in their granules. The objective was to verify the efficacy of fluticasone propionate aqueous nasal spray in patients with allergic rhinitis; in a retrospective study, we have evaluated mediators of inflammation, making correlations with the clinical symptoms score during and outside the pollen season. METHODS: Forty patients with allergic rhinitis and 15 normal controls were included in our study. Eosinophil cationic protein, eosinophil chemotactic activity, and blood and nasal lavage eosinophil count were evaluated as laboratory parameters. RESULTS: We found a significant increase in nasal lavage levels of eosinophil cationic protein in allergic patients, and this was strictly correlated with the clinical symptoms score. No differences were found in the eosinophil count of allergic patients and in the serum eosinophil cationic protein of patients sensitized to seasonal allergens in comparison with normal subjects. By contrast, an increase in serum eosinophil cationic protein level was found in patients sensitized to perennial allergens. After topical administration of fluticasone propionate aqueous nasal spray, a reduction in nasal lavage eosinophil cationic protein secretion was obtained with a reduction of eosinophil chemotactic activity at the local level. This reduction correlated with an improvement of clinical symptoms. CONCLUSIONS: The clinical improvement and reduction in nasal lavage eosinophil cationic protein and eosinophil chemotactic activity after administration of fluticasone propionate aqueous nasal spray further confirms the role of this treatment in allergic rhinitis.


Assuntos
Androstadienos/uso terapêutico , Antialérgicos/uso terapêutico , Eosinófilos/imunologia , Rinite Alérgica Perene/tratamento farmacológico , Rinite Alérgica Sazonal/tratamento farmacológico , Ribonucleases , Administração Intranasal , Adolescente , Adulto , Androstadienos/administração & dosagem , Antialérgicos/administração & dosagem , Proteínas Sanguíneas/biossíntese , Quimiotaxia , Criança , Proteínas Granulares de Eosinófilos , Eosinofilia/tratamento farmacológico , Eosinofilia/imunologia , Feminino , Fluticasona , Humanos , Masculino , Pessoa de Meia-Idade , Líquido da Lavagem Nasal/citologia , Líquido da Lavagem Nasal/imunologia , Estudos Retrospectivos , Rinite Alérgica Perene/imunologia , Rinite Alérgica Sazonal/imunologia
13.
Cardiologia ; 39(12 Suppl 1): 369-73, 1994 Dec.
Artigo em Italiano | MEDLINE | ID: mdl-7634298

RESUMO

The extracellular matrix plays an important role in biological processes, for example cellular adhesion, proliferation, migration and differentiation. Many of the cell-cell and cell-matrix interactions are mediated by extracellular matrix components and by their respective membrane receptors. Important pathophysiological processes occur through these interactions of which ontogenesis tissue differentiation and reconstruction, many inflammatory and immunological events and metastatic processes and invasion. The myocardium is made of muscular, vascular and connective components that exist in a state of equilibrium based on their relative proportions, integral structures, and on their physical and chemical characteristics. The Authors have described molecular events that lead to the organization of the cardiac tissue in physiological conditions and to its reorganization in pathological situation. Furthermore they have evaluated the role of fibronectin, a glycoprotein of the extracellular matrix in the initial phase of cardiac ischemia.


Assuntos
Espaço Extracelular , Coração/fisiologia , Miocárdio/ultraestrutura , Humanos
14.
Int J Immunopathol Pharmacol ; 15(3): 225-232, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12575923

RESUMO

We tested the hypothesis of beneficial effects of the calcium-blocker verapamil in a model of ischemia-reperfusion, and investigated its effects against coronary microcirculation and cardiomyocyte apoptosis. Isolated working rat hearts were subjected to 15 min global ischemia and 22-180 min reperfusion in the presence or absence of verapamil (0.25 &mgr;M). We evaluated creatinephosphokinase (CK) in coronary effluent, heart weight changes, microvascular permeability (extravasation of fluoresceine-labeled albumin), ultrastructural alterations, and cardiomyocyte apoptosis (by 1.5% agarose gel electrophoresis and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labelling technique). In this model, 0.25 &mgr;M verapamil significantly reduced myocardial damage, CK release and vascular hyperpermeability, concomitant with a reduction in endothelial and cardiomyocyte lesions; on the contrary, 0.25 &mgr;M verapamil was unable to reduce cardiomyocyte apoptosis. In conclusion, in the absence of perfusing granulocytes, the acute administration of a pharmacologically relevant verapamil concentration reduces ischemia-reperfusion injury and prevents coronary endothelial cell and cardiomyocyte necrotic cell death but it is unable to reduce apoptotic cell death in isolated working rat hearts.

15.
Cardiologia ; 42(8): 855-61, 1997 Aug.
Artigo em Italiano | MEDLINE | ID: mdl-9312412

RESUMO

Left ventricular remodeling, through long-term left ventricular chamber dilation and increased wall stress can result in alteration of ventricular architecture and impairment of systolic and diastolic performance. Most of the studies regard post acute myocardial infarction remodeling, knowledge is still lacking about preoperative and postoperative factors which predict the long-term prognosis of patients who underwent venous coronary artery bypass graft surgery. We evaluated 243 patients (225 males, 18 females, mean age 65 +/- 7.3 years) submitted to venous coronary artery bypass graft surgery and 10-year follow-up (123 +/- 20 months). Global mortality was 17.6% (n = 43), significantly higher in patients with ejection fraction (EF) < 50% (log-rank test p < 0.001). The survivors (n = 200) were subdivided into two groups according to postoperative EF: patients with EF > or = 50% (n = 160) and patients with EF < 50% (n = 40). Multivariate analysis revealed that cardiovascular risk factors (hypertension, diabetes, hypercholesterolemia, smoking), number of grafts and infarct location were not associated with EF reduction. Only multivessel disease was significantly associated with EF reduction (p = 0.008). Preoperative echocardiographic parameter analysis evidenced that regional ventricular wall motion score was significantly higher in patients with reduced EF (EF < 50% 11 +/- 7.5; EF > or = 50% 6 +/- 4.1, p < 0.001) and left ventricular dilation (p < 0.001). Multivariate analysis revealed that the strongest correlates of EF < 50% were left ventricular wall motion score index > 10 (odds ratio 5.8, 95% confidence interval 2.8-11.7) and multivessel disease (odds ratio 9.0, 95% confidence interval 2.6-31.08). This study revealed that echocardiographic detection of preoperative ventricular wall motion score may be useful to assess patients at high risk of ventricular remodeling after venous coronary artery bypass graft surgery.


Assuntos
Ponte de Artéria Coronária/métodos , Revascularização Miocárdica/métodos , Disfunção Ventricular Esquerda/cirurgia , Idoso , Ecocardiografia Doppler , Feminino , Seguimentos , Ventrículos do Coração/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada
16.
Cardiologia ; 44(7): 667-74, 1999 Jul.
Artigo em Italiano | MEDLINE | ID: mdl-10476593

RESUMO

BACKGROUND: The aim of this study was to evaluate, in the model of isolated working rat heart, the effects of verapamil on postischemic changes in cardiac mechanical function and microvascular coronary permeability, and the possible role of nitric oxide. METHODS: We used 72 male Wistar rats, weighing 250-300 g, divided into six groups: Group A, hearts perfused with modified Krebs-Henseleit solution (KH); Group B, hearts perfused with KH + verapamil 0.25 microM; Group C, hearts perfused with KH + verapamil 0.5 microM; Group D, hearts perfused with KH + verapamil 1 microM; Group E, hearts perfused with KH + NG-nitro-L-arginine methyl ester (L-NAME) 30 microM; Group F, hearts perfused with KH + verapamil 0.25 microM + L-NAME 30 microM. Hemodynamic parameters, necrosis enzyme release and fluoroscein isothiocyanate-albumin extravasation were evaluated. RESULTS: We observed a clear preservation of cardiac mechanical function and microvascular function in Group B (low dose verapamil) compared to groups A (control), C and D (high dose verapamil); the inhibition of nitric oxide-synthase in the presence of verapamil, obtained in Group F, elicited a loss of myocardial protective effects of verapamil. CONCLUSIONS: Our data suggest that low dose verapamil is effective on postischemic damage reduction and most probably nitric oxide plays a determinant role in this effect.


Assuntos
Bloqueadores dos Canais de Cálcio/farmacologia , Circulação Coronária/efeitos dos fármacos , Isquemia Miocárdica/fisiopatologia , Óxido Nítrico/fisiologia , Verapamil/farmacologia , Animais , Circulação Coronária/fisiologia , Técnicas In Vitro , Masculino , Microcirculação/efeitos dos fármacos , Microcirculação/fisiopatologia , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Óxido Nítrico Sintase/antagonistas & inibidores , Óxido Nítrico Sintase/efeitos dos fármacos , Ratos , Ratos Wistar
17.
Cardiologia ; 42(11): 1173-8, 1997 Nov.
Artigo em Italiano | MEDLINE | ID: mdl-9534310

RESUMO

The effect of cardiac dopaminergic receptors stimulation with epinine (N-methyldopamine) on reperfusion injury was investigated in isolated working rat heart submitted to 15 min of global ischemia. Isolated Wistar rat hearts (n = 75) were used and subdivided into five groups: Group A control hearts, Group B epinine 10 ng/ml, Group C epinine 20 ng/ml, Group D epinine 40 ng/ml, Group E epinine 80 ng/ml. The drug was added to the perfusion buffer at the beginning of experimental procedures. Hemodynamic parameters, heart rhythm (epicardial ECG), heart weight changes, coronary microvascular permeability (FITC-albumin diffusion) and myocytes damage (necrosis enzymes release, immunoperoxidase labeling anti-LDH antibody) were evaluated. After ischemia in groups B and C a significant reduction of functional alterations and myocytes damage was observed with respect to Group A associated with a significant reduction of reperfusion edema (heart weight: Group A +29 +/- 3.5%, Group B +15 +/- 3.8%, Group C 16 +/- 5%, Group D 27 +/- 5%, Group E 33 +/- 4%). At reperfusion time, a significant proarrhythmic effect occurred only in groups D and E. A significant reduction of postischemic endothelial FITC-albumin diffusion was also observed in groups B and C (FITC-albumin diffusion, Group A 32.8 +/- 6% area, Group B 16.33 +/- 5% area, Group C 21.7 +/- 4.5% area, Group D 30 +/- 5% area, Group E 35 +/- 7% area). Our data show that, in isolated working rat heart, the dopaminergic stimulation with low-doses epinine may exert a cardioprotective effect against ischemia-reperfusion damage by modulating endothelial permeability changes and improving coronary microcirculation. The importance of dopaminergic receptors is also suggested by the evidence that at higher doses, when alpha and beta-adrenoceptors stimulation occurs, this cardioprotective effect is significantly reduced or lost.


Assuntos
Desoxiepinefrina/uso terapêutico , Agonistas de Dopamina/uso terapêutico , Endotélio Vascular/efeitos dos fármacos , Isquemia Miocárdica/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Animais , Endotélio Vascular/patologia , Técnicas In Vitro , Masculino , Isquemia Miocárdica/patologia , Traumatismo por Reperfusão Miocárdica/patologia , Ratos , Ratos Wistar
18.
Cardiologia ; 39(12 Suppl 1): 381-8, 1994 Dec.
Artigo em Italiano | MEDLINE | ID: mdl-7634300

RESUMO

Myocardial interstitium plays an important role in the regulation of cardiac function compared with myocytes and it is actively involved in ischemia-reperfusion damage and in the acute and chronic remodelling during ischemic heart diseases. Myocardial post-ischemic oedema seems to interfere in this process. Myocardial oedema is able to induce structural alterations, to reduce myocardial function and to activate the renin-angiotensin-aldosterone system. Angiotensin II and aldosterone seem to be the cause of myocardial fibrosis that is detected during ischemic heart disease. Post-ischemic vascular permeability alterations have a similar role. In clinical conditions, ACE-inhibitors have important effects on cardioreparation and are able to improve cardiac function and reduce early and late mortality. The effects of myocardial oedema reduction (i.e. hypertonic reperfusion) on ischemia-reperfusion damage and myocardial fibrosis are still to clarify. A reduction in myocardial fibrosis may improve cardioreparation and prevent congestive heart failure, following ischemic heart disease.


Assuntos
Espaço Extracelular , Miocárdio/patologia , Traumatismo por Reperfusão/patologia , Doença Aguda , Doença Crônica , Ventrículos do Coração/patologia , Humanos , Infarto do Miocárdio/patologia , Isquemia Miocárdica/patologia , Necrose , Traumatismo por Reperfusão/fisiopatologia , Traumatismo por Reperfusão/prevenção & controle
19.
Cardiologia ; 38(2): 107-12, 1993 Feb.
Artigo em Italiano | MEDLINE | ID: mdl-8391928

RESUMO

The protective effects of captopril were evaluated in vitro on isolated perfused rat hearts after a global ischemia of 20 min. The hearts were randomly allocated in 2 groups. In the first one (n = 6) captopril was added at a concentration of 270 microM. The second one was utilized as control (n = 6). Aortic flow and minute work respectively decreased on reperfusion by 35% and 49% in captopril group and by 65% and 71% in controls (p < 0.001). No changes occurred in heart rate. Aortic systolic pressure and coronary flow decreased in the 2 groups, but not significantly. Myocardial enzyme release during reperfusion showed significant lower levels of CPK and LDH in the captopril group as compared to controls (p < 0.001 after 41 min). The occurrence of serious ventricular arrhythmias was considerably higher in controls with respect to the captopril group. Irreversible ventricular fibrillation occurred only in control hearts (50%). These data indicate that captopril exerts a protective effect during myocardial ischemia and reperfusion by preventing serious ventricular arrhythmias, reducing enzymatic release and a lower decrease in cardiac performance, without an increase in heart rate.


Assuntos
Captopril/uso terapêutico , Coração/efeitos dos fármacos , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miocárdio/enzimologia , Peptidil Dipeptidase A/metabolismo , Animais , Creatina Quinase/efeitos dos fármacos , Creatina Quinase/metabolismo , Avaliação Pré-Clínica de Medicamentos , Hemodinâmica/efeitos dos fármacos , Técnicas In Vitro , L-Lactato Desidrogenase/efeitos dos fármacos , L-Lactato Desidrogenase/metabolismo , Masculino , Traumatismo por Reperfusão Miocárdica/enzimologia , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Peptidil Dipeptidase A/efeitos dos fármacos , Distribuição Aleatória , Ratos
20.
Cardiologia ; 40(2): 101-7, 1995 Feb.
Artigo em Italiano | MEDLINE | ID: mdl-7671273

RESUMO

Degenerative aortic stenosis represents the most common form of aortic stenosis. The aim of this study was to evaluate the relationship between symptoms, valvular disease severity and prognosis. We studied the evolution of valvular aortic stenosis in 65 patients (39 males and 26 females, mean age 77.78 +/- 6.2 years) for a period of 7 years. All patients were submitted to accurate anamnestic examination, ECG, color Doppler echocardiography. Sixteen patients (26%) underwent cardiac catheterization. Associated diseases were: hypertension (45%), diabetes (40%), dyslipidemia (29%), chronic obstructive lung disease (6%). In 64% patients, the diagnosis of aortic stenosis was made after symptoms onset, and in 36% was occasional. Mean age at symptoms onset was 70 +/- 17 years: dispnoea was present in 81%, chest pain in 32%, and syncope in 8%. At the beginning of the follow-up, echocardiography showed, aortic stenosis to be mild in 21.73%, moderate in 60.8% and severe in 17.4%. At the end of the follow-up, mild stenosis was present in 9.5%, moderate in 38.7%, and severe in 51.8%. At entry, 56.6% had pure aortic stenosis, 34.78% had steno-insufficiency and 8.7 had an associated mitral valve insufficiency. At the end of the follow-up pure aortic stenosis was present in 17%, steno-insufficiency in 40%, and associated mitral valve insufficiency in 4.3%. Surgery was performed in 21% of the patients (77% valve replacement and 23% valve replacement and aortocoronary bypass). The mortality, at the end of the follow-up, was 31%. Causes of death were: heart failure (61%), arrhythmias (23%), and surgical complications (16%).(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Estenose da Valva Aórtica/terapia , Idoso , Idoso de 80 Anos ou mais , Estenose da Valva Aórtica/mortalidade , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Taxa de Sobrevida
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