RESUMEN
The mechanism of the positive inotropic effect of prostacyclin (PGI2) (2.6 x 10(-6) mol/l) on the isolated right ventricle of rat heart was studied. Our results show that the positive inotropic effect of prostacyclin is produced indirectly through beta adrenoceptors and slow Ca2+ channels, because blockade of slow Ca2+ channels with verapamil (10(-6) mol/l) and beta adrenoceptors with propranolol (10(-6) mol/l) abolishes this effect. Alpha adrenoceptors do not mediate the action of PGI2.
Asunto(s)
Epoprostenol/farmacología , Contracción Miocárdica/efectos de los fármacos , Antagonistas Adrenérgicos alfa/farmacología , Antagonistas Adrenérgicos beta/farmacología , Animales , Antihipertensivos/farmacología , Bloqueadores de los Canales de Calcio/farmacología , Técnicas In Vitro , Prazosina/farmacología , Propranolol/farmacología , Ratas , Ratas Wistar , Vasodilatadores , Verapamilo/farmacologíaRESUMEN
The experiments done on the isolated right ventricle of rat heart suspended in the bath for isolated organs with oxygenated Tyrode's solution showed the PgI2 (2.3 x 10-6 mmol) produced its positive inotropic effect indirectly by promoting both beta-adrenoreceptors and calcium entry through slow calcium channels because this effect could be blocked by propranolol (2.3 x 10-2 mmol - beta-adrenoreceptor blocker) or verapamil (4.3 x 10-3 mmol - slow calcium channel blocker).
Asunto(s)
Epoprostenol/farmacología , Contracción Miocárdica/efectos de los fármacos , Agonistas Adrenérgicos beta/farmacología , Animales , Calcio/metabolismo , Técnicas In Vitro , Propranolol/farmacología , Ratas , Ratas Endogámicas , Función Ventricular Derecha/efectos de los fármacos , Verapamilo/farmacologíaRESUMEN
Antitoxinum viperinum was tested for its ability to prevent alteration of the myocardium induced by Vipera ammodytes ammodytes venom. Antivenom was injected intraperitoneally either immediately, 30 min or 2 hr after the intraperitoneal injection of venom. The light microscopic examination showed that the antiserum neutralized the effects of venom and antivenom might be useful in treating V.a. ammodytes venom poisoning.