Abstract
Eight mongrel dogs were operated to produce pulmonary stenosis. Eight weeks after the operation, the free wall of the right ventricle with myocardial lesions was excised and a strip of the muscle was prepared for this study. The preparations immersed in oxygenated Tyrode's solution were given several drugs, such as Thiamine pyrophosphate (Cocarboxylase), Thiamine Tetrahydrofurfuryl Disulfide (TTFD), Thiamine Propyl Disulfide (TPD), Thimamine hydrochloride. Adenosine Triphosphate (ATP) and Desacetyl-lanatoside C (Lanatoside C). The effect of these drugs on specimens were observed electrophysiologically regarding transmembrane action potential, its duration and contractile tension as compared with the normal heart muscle.
