Effects of ritanserin on transmembrane action potentials in canine Purkinje fibers.

Ritanserin has been reported to be a potential antiarrhythmic. We studied the cellular electrophysiologic effects of ritanserin in canine Purkinje fibers. Ritanserin produced significant depressant effects on transmembrane action potentials elicited in canine Purkinje fibers.

Synthesis, calcium-channel-blocking activity, and antihypertensive activity of 4-(diarylmethyl)-1-[3-(aryloxy)propyl]piperidines and structurally related compounds.

A series of 4-(diarylmethyl)-1-[3-(aryloxy)propyl]piperidines and structurally related compounds were synthesized as calcium-channel blockers and antihypertensive agents. Compounds were evaluated for calcium-channel-blocking activity by determining their ability to antagonize calcium-induced contractions of isolated rabbit aortic strips. The most potent compounds were those with fluoro substituents in the 3- and/or 4-positions of both rings of the diphenylmethyl group.

AHR-16303B, a novel antagonist of 5-HT2 receptors and voltage-sensitive calcium channels.

In vivo and in vitro methods were used to characterize AHR-16303B, a novel compound with antagonistic action at 5-HT2 receptors and voltage-sensitive calcium channels. The 5-HT2 receptor-antagonistic properties of AHR-16303B were demonstrated by inhibition of (a) [3H]ketanserin binding to rat cerebral cortical membranes (IC50 = 165 nM); (b) 5-hydroxytryptamine (5-HT)-induced foot edema in rats (minimum effective dose, (MED) = 0.32 mg/kg orally, p.

AHR-14310C: a potent, long-acting, nonsedating H1-antihistamine that prevents antigen-induced mucus formation in sensitive rats.

AHR-14310C(5-[2-[4-[bis(4-fluorophenyl)hydroxymethyl- 1-piperidinyl]ethyl]-3-methyl]-2-oxazolidinone ethanedioate, hydrochloride salt) displays potent and long-acting antihistaminic activity in guinea pigs and in dog and guinea pig models of immediate hypersensitivity. Given orally 1, 5 or 24 hr before an i.v.

A dual electrophysiologic test for atrial antireentry and ventricular antifibrillatory studies. Effects of bethanidine, procainamide, and WY-48986.

We have developed a dual electrophysiologic test that allows measurement of both antireentry and antifibrillatory activities of potential antiarrhythmics in the same anesthetized dog. The reentry portion of the model was created surgically by a Y-shaped crushing around the tissue between the superior and inferior vena cava and tissue parallel to the AV groove. The pacing-induced tachycardia that results from circus movements around the tricuspid ring is very persistent in duration and regular in cycle length.