Transmembrane Potentials in Bovine Lymphatic Smooth Muscle

Abstract

Summary

Transmembrane potentials in smooth muscle fiber of bovine mesenteric lymphatics have been studied with the aid of an intracellular microelectrode technique. Resting potentials ranged from −41 to −57 mV. In most of the preparations, the slow fluctuations in the resting potentials were recognized, amplitude and duration of which were about 10 mV and 400-1200 msec, respectively. A burst of action potentials was associated with a spontaneous contraction wave. The amplitude of the action potentials ranged from 39 to 57 mV. The duration of the action potentials was 47.8 ± 9.4 msec in 10 experiments. The magnitude of occasional overshoot was a few millivolts. The level of the resting potentials and the configuration of the action potentials were not affected by tetrodotoxin.