Gallamine triethiodide (flaxedil): tetraethylammonium- and pancuronium-like effects in myelinated nerve fibers.
Gallamine triethiodide (Flaxedil) is commonly used as a neuromuscular blocking agent. Voltage-clamp studies show that gallamine also directly affects amphibian and mammalian myelinated nerve fibers. Externally, gallamine is about five times more potent than tetraethylammonium in blocking potassium conductance, where this is present, but has no effect on the sodium channel. Internal application slows sodium inactivation, which in addition is often incomplete. At positive potentials, gallamine can occlude sodium channels, thereby almost eliminating outward sodium currents.
D000818:Animals; D004553:Electric Conductivity; D005703:Gallamine Triethiodide / Q000494:pharmacology*; D008564:Membrane Potentials / Q000187:drug effects; D009186:Myelin Sheath / Q000187:drug effects / Q000502:physiology*; D009474:Neurons / Q000502:physiology*; D010197:Pancuronium / Q000494:pharmacology; D011188:Potassium / Q000494:pharmacology; D011898:Ranidae; D051381:Rats; D012964:Sodium / Q000378:metabolism; D013757:Tetraethylammonium Compounds / Q000494:pharmacology
D013757:Tetraethylammonium Compounds; D012964:Sodium; D010197:Pancuronium; D005703:Gallamine Triethiodide; D011188:Potassium