[Pharmacological Properties of Fendiline in Cardiac and Smooth Muscle (author's transl)].

The pharmacological properties of fendiline N-(1-phenylethyl [1])-3,3 - diphenylpropylamine-hydrochloride; Sensit, were investigated in the isolated guinea pig heart and in isolated circular smooth muscle strips of bovine coronary arteries, pulmonary arteries and trachea. 1. Fendiline dose dependently increased coronary flow by up to 200% but, different from verapamil, did not inhibit contraction. 2. Fendiline dose dependently relaxed coronary strips and, more powerfully, tracheal and pulmonary arterial strips. 3. In cardiac muscle, fendiline was almost completely retained for a prolonged period of time. In the smooth muscle tissues under study, fendiline accumulated twenty-fold above the concentration present in the organ bath. 4. In paced hearts, fendiline non-competitively inhibited the positive inotropic effect of isoprenaline in doses that did not significantly depress the amplitude of isotonic contractions. 5. In the guinea pig heart, adenosine uptake becomes progressively inhibited when coronary flow increases. This "washout" effect was definitely counteracted by fendiline and by NaNO2, but was augmented by papaverine, hexobendine and dipyridamol. The counteraction of the "washout effect" by fendiline as well as by NaNO2 is most likely due to the opening of additional (previously closed) capillaries.