The calcium-dependent slow after-hyperpolarization in myenteric plexus neurones with tetrodotoxin-resistant action potentials.
Intracellular recordings were made from neurones of the myenteric plexus of the guinea-pig ileum. The slow after-hyperpolarization which followed an action potential in some neurones was abolished by Mn(++), La(+++) and by solutions which contained no Ca(++). In these neurones, the action potential and the slow after-hyperpolarization persisted in Na(+)-free solutions or in the presence of tetrodotoxin (2 muM). The findings suggest that an inward Ca(++) current during the action potential is essential for the slow after-hyperpolarization.
D000200:Action Potentials / Q000187:drug effects*; D000818:Animals; D002118:Calcium / Q000502:physiology*; D006168:Guinea Pigs; D007811:Lanthanum / Q000494:pharmacology; D008345:Manganese / Q000494:pharmacology; D008839:Microelectrodes; D009197:Myenteric Plexus / Q000502:physiology*; D012964:Sodium / Q000494:pharmacology; D013779:Tetrodotoxin / Q000494:pharmacology*
D008345:Manganese; D013779:Tetrodotoxin; D007811:Lanthanum; D012964:Sodium; D002118:Calcium