Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0042510 (ventricular fibrillation)
 10,091 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Forty anaesthetized dogs were subjected to left circumflex coronary artery ligation followed by reperfusion. Molsidomine was randomly administered to 20 dogs (50 micrograms kg-1 as an i.v. bolus - 15 min prior to coronary occlusion - followed by an infusion of 0.05 micrograms kg-1 min-1. Standard electrocardiographic leads 2 and 3 were continuously recorded to measure ST segment and delta R% changes and to document both the number of ventricular premature beats and the onset of ventricular fibrillation; aortic pressure and cardiac output were measured; thromboxane B2 plasma levels, platelet aggregation produced by ADP, and molsidomine plasma levels were determined before and at 10, 30 and 75 min after the start of the drug protocol. Molsidomine protected the treated animals from early (10 min) post-ischaemic ventricular fibrillation (0 of 20 vs 6 of 20, P = 0.0202), reduced the incidence of overall post-occlusion ventricular fibrillation (3 of 20 vs 10 of 20, P = 0.0407) and improved the total survival rate (P = 0.0067). In molsidomine treated dogs: mean aortic pressure and the rate-pressure product were lowered 10 min after the start of the drug; immediate post-occlusion (3 min) ST segment changes (0.82 +/- 0.52 vs 1.52 +/- 0.78 mV, P less than 0.025) and delta R% changes (37 +/- 50 vs 90 +/- 84%, P less than 0.025) were less marked; the number of ventricular premature beats was lowered and finally, a progressive decline of platelet aggregation produced by ADP was achieved after 75 min of drug infusion. These results were obtained in the presence of mean plasma levels of molsidomine ranging from 20 to 28 ng ml-1. The time-action curve of the antifibrillatory effect of molsidomine parallels those at the level of post-ischaemic electrocardiographic changes.
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PMID:Molsidomine prevents post-ischaemic ventricular fibrillation in dogs. 375 34

The cardioprotective and antithrombotic activity of molsidomine, a novel therapeutic agent for the treatment of coronary heart disease, was investigated in a series of animal models of myocardial ischemia. Molsidomine given to dogs with marked ST segment elevation (epicardial electrogram), induced by a reduction of left descending coronary artery (LAD) flow to 20% to 30% of the original value, resulted within 40 minutes in complete normalization of ECG changes. In another animal model molsidomine given either before or after occlusion of the LAD significantly reduced infarct size. All these molsidomine effects were accompanied by a marked lowering of preload, resulting in a reduction of extravascular coronary artery resistance and in increased blood flow toward the ischemic zones. In a model of myocardial ischemia and reperfusion in the anesthetized dog, molsidomine had a marked protective effect against the incidence of spontaneous ventricular fibrillation. This effect could also be attributed to the anti-ischemic activity of molsidomine, which would reduce the disparity between the refractory periods in normal and ischemic areas and thus increase ventricular stability. The antithrombotic activity of molsidomine was investigated in dogs in which the left circumflex coronary artery was electrically stimulated, a procedure that leads to thrombotic occlusion. Molsidomine in a dose-dependent manner prevented coronary thrombotic occlusion and reduced thrombus wet weight and the size of the resulting infarction. These effects of molsidomine were not related to its hemodynamic activity, since nitroglycerin and isosorbide dinitrate had similar hemodynamic effects but did not prevent coronary thrombosis. The antithrombotic activity of molsidomine is probably related to its ability to lower coronary venous blood thromboxane levels.
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PMID:The activity of molsidomine in experimental models of ischemic cardiac disease. 391 49

The effect of the novel antianginal agent molsidomine on the incidence of spontaneous ventricular fibrillation during myocardial ischemia and reperfusion was investigated in the anesthetized dog. Molsidomine was administered as an intravenous bolus at the dose of 0.05 mg/kg. Twenty minutes later, the left anterior descending coronary artery was occluded for 90 min. During the occlusion period, molsidomine was given as a continuous intravenous infusion at the dose of 0.5 micrograms/kg per ml per min. After release of the occlusion, the animals that survived were monitored for another 30 min. Control animals received saline. In the control animals, coronary occlusion was accompanied by an increase in heart rate, heart contractility, left ventricular end-diastolic pressure, and blood pressure as well as by ventricular arrhythmias. Molsidomine either abolished or reduced both hemodynamic and electrical changes. During the reperfusion period, 10 out of 12 control animals died, and the deaths were from ventricular fibrillation; one out of eight molsidomine-treated animals also died of ventricular fibrillation. It is postulated that the protective effect of molsidomine rests on its hemodynamic effects resulting in a shift in blood flow toward the ischemic zones and, consequently, in an increase in ventricular electrical stability.
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PMID:Effect of molsidomine on spontaneous ventricular fibrillation following myocardial ischemia and reperfusion in the dog. 668 49

This paper is a synopsis on recent reports dealing with the pharmacological basis of molsidomine-induced circulatory effects. The therapy of coronary insufficiency by molsidomine is based on different pathophysiological and pharmacological mechanisms. The inactive compound molsidomine is metabolized--mainly in the liver--to form the vasoactive and antiaggregatory compound SIN-1 and SIN-1A. Due to the gradual conversion into the active compound, the peak effects are observed only after 15 min (intravenously) or 30 to 60 min (orally). The effects are long-lasting and can be observed up to four to six hours. The c-GMP mediated dilation of various vascular sites comprise mainly the venous system (both small and large veins), resulting in a significant preload reduction, a decrease in cardiac output, a decrease in heart size and circumferential wall stress, a decrease in myocardial oxygen consumption and a therapeutically important improvement of O2-delivery versus myocardial O2-consumption. This effect results in a significant improvement of myocardial ischemia (reducing frequency of anginal attacks, improvement of exercise tolerance and of exercise induced ST-depressions). In animal experiments molsidomine diminishes infarct size and suppresses reperfusion-induced ventricular fibrillation following ischemia. Molsidomine dilates, like nitroglycerin, the large coronary arteries. Therefore, in coronary heart disease, it may improve collateral flow in addition to beneficial effects on subendocardial perfusion resulting from the reduction of ventricular wall stress. In addition to direct dilating effects on collateral vessels an improvement in perfusion of asynergistically contracting ventricular sections has been observed. In contrast to nitroglycerin, effects on peripheral resistance appear only under extremely high dosages and reflex increases in heart rate are rarely observed. In general molsidomine-induced changes (increases) in heart rate, in stroke volume (decreases), and in cardiac output (decreases) are of small magnitude. Recently interesting findings on molsidomine-induced suppression of thrombocyte aggregation, of thromboxan-synthesis inhibition and of increased prostacyclin formation have been presented, which may be important in the improvement of myocardial (micro-) circulation under ischemic conditions.
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PMID:[Pharmacological basis of therapy with molsidomine]. 689 44