RESUMO
The effect of different doses of perfluorocarbon emulsion (5, 10, and 15 ml/kg) on the hemodynamics and contractility of heart was studied on anesthetized dogs. The emulsion was introduced intravenously by the 60th minute of acute myocardium ischemia caused by partial coronary occlusion. When pO2 = 120 mm Hg, the emulsion was efficient only at doses of 10 and 15 ml/kg (an increase in cardiac ejection, in the rate of contraction and relaxation of the myocardium, reduction of vascular resistance). However, the efficiency of the emulsion at a dose of 15 ml/kg was lower, possibly, due to hypervolemia and cardiodepressive effect of introduction of excess quantity of the surface-active substance proxanol, a component of the emulsion.
Assuntos
Fluorocarbonos/farmacologia , Coração/efeitos dos fármacos , Contração Miocárdica , Isquemia Miocárdica/prevenção & controle , Animais , Cães , Emulsões , Feminino , Fluorocarbonos/administração & dosagem , Hemodinâmica/efeitos dos fármacos , Masculino , Isquemia Miocárdica/fisiopatologiaRESUMO
The anti-ischemic effect of a 4% proxanol solution (intravenous injection in a dose of 10 ml/kg 60 min after occlusion) was compared with that of a salt solution in experimental acute ischemia of dog myocardium, induced by partial occlusion of the anterior descending branch of the left coronary artery. Overall estimation of the effect of SAS infusion has demonstrated that this drug has a beneficial effect on hemorheology (decreases blood viscosity and vascular resistance, increases coronary blood flow), stabilizes oxygen supply of the myocardium and lowers the extent of its ischemia-induced damage (eliminates ST segment depression). However, the cardiodepressive action of proxanol does not allow for compensation of the ischemia-induced decrease in myocardial contractility and pump function of the heart.
Assuntos
Coração/efeitos dos fármacos , Isquemia Miocárdica/tratamento farmacológico , Poloxaleno/farmacologia , Animais , Cães , Avaliação Pré-Clínica de Medicamentos , Eletrocardiografia/efeitos dos fármacos , Feminino , Coração/fisiologia , Hemodinâmica/efeitos dos fármacos , Masculino , Isquemia Miocárdica/sangue , Isquemia Miocárdica/fisiopatologia , Miocárdio/metabolismo , Poloxaleno/uso terapêuticoRESUMO
On the 60th minute after inducing the acute ischemia in the canine myocardium by the occlusion of the left anterior descending coronary artery, the animals were intravenously infused with perfluorochemical emulsion (PFCE), its salt composition (SC) or 4% surface-active substance (SAS), proxanol, at a dose of 10 ml/kg. Two hours after infusion, the occlusion was removed (reperfusion). The arterial pO2 was maintained at 120 mm Hg. Analysis of the blood flow, oxygen supply, acid-alkali balance, ECG, as well as creatine phosphokinase activity, measured in the ischemic area, has shown that PFC emulsion is capable of reducing ischemic damage and preventing reperfusion-induced myocardium injury. Thus, the presence of perfluorochemicals in the PFC emulsion is an essential factor in its ischemia-protective effect.
Assuntos
Doença das Coronárias/prevenção & controle , Fluorocarbonos/uso terapêutico , Coração/efeitos dos fármacos , Animais , Transporte Biológico/efeitos dos fármacos , Viscosidade Sanguínea/efeitos dos fármacos , Dióxido de Carbono/sangue , Doença das Coronárias/metabolismo , Cães , Avaliação Pré-Clínica de Medicamentos , Emulsões , Feminino , Masculino , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Miocárdio/metabolismo , Oxigênio/sangue , Consumo de Oxigênio/efeitos dos fármacos , Fatores de TempoAssuntos
Fluorocarbonos/farmacologia , Modelos Cardiovasculares , Contração Miocárdica/efeitos dos fármacos , Músculos Papilares/efeitos dos fármacos , Potenciais de Ação/efeitos dos fármacos , Potenciais de Ação/fisiologia , Animais , Emulsões , Fluorocarbonos/administração & dosagem , Técnicas In Vitro , Contração Miocárdica/fisiologia , Músculos Papilares/fisiologia , Perfusão , CoelhosRESUMO
Acute myocardial ischemia was induced by reducing the lumen of the anterior descending branch of the left coronary artery in 32 mongrel dogs. Following 60 min of ischemia, 16 animals were infused perfluorine carbon emulsion (10 ml/kg) and 16 were given saline. Alteration in hemodynamics, myocardial contractility, coronary blood flow, as well as pH and pO2 in the ischemic area were examined. The analysis of the results showed that carbon tetrafluoride emulsion, in contrast to saline, substantially increased coronary blood flow and oxygen supply in the ischemic area decreased myocardial ischemic and reperfusion lesion, improved hemodynamic parameters and myocardial contractility.
Assuntos
Doença das Coronárias/tratamento farmacológico , Fluorocarbonos/uso terapêutico , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Animais , Circulação Coronária/efeitos dos fármacos , Cães , Emulsões , Fluorocarbonos/administração & dosagem , Estimulação QuímicaRESUMO
The study was conducted to determine if myocardium can be protected against ischemic and reperfusion damage by means of the preliminarily injected perfluorocarbon emulsion. Injection of the emulsion into rabbit 1, 12, 24 h prior to ischemia was found to decrease the extent of ischemic and reperfusion damage to myocardium. The cardiotropic effect of the injected emulsion is shown to be dose- and time dependent.
Assuntos
Fluorocarbonos/farmacologia , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Animais , Emulsões , Fluorocarbonos/administração & dosagem , Fluorocarbonos/sangue , Coração/efeitos dos fármacos , Técnicas In Vitro , Contração Miocárdica , Miocárdio/citologia , Coelhos , Espectrofotometria , Fatores de TempoRESUMO
The authors studied the possibility of prolonged (24-hour) storage of the myocardium by means of the Soviet-produced emulsion based on perfluoro-methyl-cyclohexylpiperidine (PFMCP). It was established that the functional condition of the myocardium is maintained on a good level by hypothermal perfusion in which the perfusion medium is a gas-transporting perfluorocarbon emulsion with hydroxyethyl starch. The successful use of the PFMCP emulsion in prolonged heart storage is linked not only with the gas-transporting and rheological properties but also with the membrane stabilizing effect of the emulsion and its components.