Mechanical and Electrical Actions of Nicotine on Hypertrophied and Failed Cat Ventricle 1

Summary Nicotine increases peak active isometric force in sham operated and RVH ventricular muscles by indirect (catecholamine-mediated) and direct effects. In such muscles, action potential plateau and action potential duration eventually lengthen during exposure to nicotine (6.2 × 10-4 M and 6.2 × 10-3 M). Muscles from cats in overt RVF showed significantly smaller transient positive inotropic responses during exposure to nicotine than sham and RVH muscles. RVF muscles demonstrated an increased maintained peak active force during exposure to 6.2 × 10-3 M nicotine.