The Mechanism of Contraction Response to EFS in Cat Esophageal Circular Muscle

Low-frequency electrical field stimulation of transmural nerves of cat esophageal circular smooth muscle produces an “off contraction”, which occurs after electirical field stimulation (EFS) of transmural nerves is stopped. We previously examined signal transduction pathways mediating ACh-induced contraction of circular smooth muscle of esophagus. The extracellular Ca$\^$2+/ is needed for the contraction, results in the activation PKC. EFS-induced contraction was abolished by the pretreatments of tetrodotoxin(1 ${\mu}$M) and atropine (1 ${\mu}$M). (omitted)