Blockade of electrophysiological properties of muscle fibres by lycorine.
This study concerns the action of the alkaloid lycorine on electrophysiological properties of single sartorius muscle fibres. Lycorine caused a decrease of the resting membrane potential, a lengthening in the rise and decay times of the action potential and a fall of the muscle accommodation. The depolarizing effect was not affected when Na+ is replaced by choline in the Ringer solution. Lycorine did not inhibit the (Na+ + K+) ATPase activity. The results suggest that action of lycorine on the electrophysiological properties can be attributed to an interference with potassium channels.
D000200:Action Potentials / Q000187:drug effects; D000251:Adenosine Triphosphatases / Q000037:antagonists & inhibitors; D000470:Alkaloids / Q000494:pharmacology*; D047151:Amaryllidaceae Alkaloids; D000818:Animals; D001001:Anura; D004305:Dose-Response Relationship, Drug; D066298:In Vitro Techniques; D008564:Membrane Potentials / Q000187:drug effects; D009132:Muscles / Q000502:physiology*; D010617:Phenanthridines / Q000494:pharmacology*
D000470:Alkaloids; D047151:Amaryllidaceae Alkaloids; D010617:Phenanthridines; D000251:Adenosine Triphosphatases; C015330:lycorine