Endothelin-1-induced depolarization and hyperpolarization in submandibular ganglion neurons.
The effects of endothelin-1 were studied in vitro on neurons in the hamster submandibular ganglion, using the intracellular microelectrode technique. Endothelin (1 microM) caused a depolarization (5.5 +/- 1.2 mV) followed by a hyperpolarization (8.5 +/- 2.8 mV) of the membrane potential. Membrane conductance was increased during the endothelin-induced depolarization and was decreased during the endothelin-induced hyperpolarization. The endothelin-induced depolarization was depressed (mean 43.6%) in a Krebs solution containing zero calcium and high magnesium. The results suggested that the predominant component of the depolarization was mediated by calcium ions. The calcium-insensitive component of depolarization was carried by chloride ions. Endothelin-induced slow rhythmic hyperpolarizations were probably induced by a decrease in chloride ion conductance.
Suzuki
Takashi
T
Department of Physiology, Tokyo Dental College, 1-2-2 Masago, Mihama-ku, Chiba 261-8502, Japan.
D000818:Animals; D002118:Calcium / Q000494:pharmacology; D002712:Chlorides / Q000494:pharmacology; D006224:Cricetinae; D019332:Endothelin-1 / Q000494:pharmacology*; D005726:Ganglia, Parasympathetic / Q000187:drug effects*; D008274:Magnesium / Q000494:pharmacology; D008564:Membrane Potentials / Q000187:drug effects; D008839:Microelectrodes; D009431:Neural Conduction / Q000187:drug effects; D009474:Neurons / Q000187:drug effects*; D013363:Submandibular Gland / Q000294:innervation*
D002712:Chlorides; D019332:Endothelin-1; D008274:Magnesium; D002118:Calcium