THE ACTION POTENTIALS ACCOMPANYING CONDUCTED RESPONSES IN VISCERAL SMOOTH MUSCLES

Abstract

The action potentials of different types of visceral smooth muscles were recorded by a d. c. amplifier and an oscillograph. Monophasic potentials of uterine and intestinal muscle consist of brief spikes resembling those of skeletal muscle, whereas in the ureter there is usually a plateau, sometimes lasting for several secs., as in cardiac muscle. The potentials of the ureter of the guinea pig are intermediate between these extremes, consisting of a repetitive discharge of spike potentials superimposed on a persistent negativity. The differences in the action potentials are correlated with other physiological properties of the muscles.