[The first original Russian class-III antiarrhythmic nibentan].

The paper presents experimental and clinical findings of the new antiarrhythmic drug nibentan. The agent was found to be a class-III antiarrhythmic agent in terms of its electrophysiological effects and an inhibitor of the delayed rectifier potassium current in terms of its effects on the ionic channels of cardiomyocytes. The clinical trial of nibentan shows that the drug is highly effective (in 70-100% of cases) in patients with atrial flutter and fibrillation and in those with supraventricular tachycardia and it is less effective in suppressing ventricular premature contractions and tachycardia.

[Proxodolol--a new beta- and alpha-adrenoblockader].

The beta- and alpha-adrenoceptor blocking activity, the specificity of its beta-adrenoceptor blocking action, partial agonistic and membrane-stabilizing properties, as well as antihypertensive, antiarrhythmic, and anti-ischemic effects were studied. Proxodolol was shown to be superior to labetalol in its beta-adrenoceptor blocking action and similar to it in its alpha-adrenoceptor blocking agent. The drug has no a partial agonistic activity and produces a moderate membrane-stabilizing action.

[Beta-adrenoblocking activity and other pharmacological properties of 2-(3-amino-2-hydroxypropoxy)phenyoxymethyl isoxazole derivatives].

Some derivatives of 2-(3-amino-2-hydroxypropoxy)phenoxymethyl isoxazole possess beta- and alpha-adrenoblocking activity. 3-Methyl-4-chlor-5-(3-isopropylamino-2-hydroxypropoxy)phenoxymethyl isoxazole hydrochloride (compound OF-4452) is the most active of the compounds studied. As to the beta-adrenoblocking activity, this compound given in vivo and in vitro compares very favourably with propranolol, oxprenolol and labetalol, in particular; as regards the alpha-adrenoblocking action, it is not inferior to the latter drug.