title: Actions of acetylcholine on the salivary gland cells of the pond snail, Planorbis corneus.
abstract: Intracellular recordings have been made from salivary gland cells of the pond snail Planorbis corneus. Gland cells produced a dose-dependent biphasic response to the bath application of acetylcholine (ACh), an initial depolarization being followed by a hyperpolarization. Nicotine and the nicotinic agonist tetramethylammonium had an excitatory action on the gland cells. The muscarinic agonists acetyl-beta-methyl choline and arecoline were also stimulants, but muscarine, bethanechol and pilocarpine produced no response from gland cells at 10(-3) M. A number of cholinergic antagonists, including atropine, hexamethonium and curare, effectively blocked the response to ACh. The depolarizing phase of the ACh response resulted from an increased membrane permeability to Na+ ions, though the participation of other ionic species cannot be ruled out. The hyperpolarizing phase of the ACh response was produced by the activity of an electrogenic Na+/K+ pump.
authors.forename: A
authors.initials: A
authors.lastname: Barber
mesh_terms: D000109:Acetylcholine / Q000494:pharmacology*; D000818:Animals; D002463:Cell Membrane Permeability / Q000187:drug effects; D004594:Electrophysiology; D005731:Ganglionic Stimulants / Q000494:pharmacology; D066298:In Vitro Techniques; D008564:Membrane Potentials / Q000187:drug effects; D009538:Nicotine / Q000494:pharmacology; D010277:Parasympathomimetics / Q000494:pharmacology; D011188:Potassium / Q000494:pharmacology; D012469:Salivary Glands / Q000166:cytology / Q000187:drug effects / Q000502:physiology; D012908:Snails / Q000187:drug effects / Q000502:physiology*; D012964:Sodium / Q000502:physiology
chemical_list: D005731:Ganglionic Stimulants; D010277:Parasympathomimetics; D009538:Nicotine; D012964:Sodium; D000109:Acetylcholine; D011188:Potassium