Effects of naftidrofuryl oxalate on peripheral circulation

Effects of i. v. or i. a. administered naftidrofuryl oxalate (LS-121; 0.1 to 1.0mg/kg) on the regional blood flow of organs of the unanesthetized, curarized cat were studied using the thermoelectrical method. Injection of LS-121 i. v. caused a moderate increase in blood flow in the myocardium and renal cortex, and a marked increase in skeletal muscle, whereas, a very slight increase or no change at all was observed in the cerebral cortex, liver, renal medulla and skin. Injection of the drug La. caused a moderate increase of blood flow in the cerebral cortex and skin, marked increase in the renal cortex and a considerable increase in the skeletal muscle, whereas little or no change was seen in the liver and renal medulla. Increase of blood flow in the skeletal muscle was partially blocked after administration of propranolol, but not after atropine. On the other hand, norepinephrine caused a decrease of blood flow in the skin. The decrease was not blocked after administration of LS-121. Systemic blood pressure began to fall when 0.5mg/kg of the drug was injected, and the fall although more apparent was temporary with a higher dose of the drug. The above mentioned results indicate that LS-121 increases the regional blood flow in organs having mainly a papaverine-like vasodilating action and partially an adrenergic beta effect on the vascular muscle.