title: Role of membrane permeabilities (calcium, chloride, and potassium) in the genesis of the notch observed on simian and prosimian cardiac action potentials.
abstract: The effect of temperature reduction on monkey ventricular action potentials has been studied. Under this condition the genesis of a notch separating the AP spike from the AP plateau has been related either to a conduction phenomenon or to a delay in the activation of the slow inward current. It is observed that the development of a notch at the beginning of the plateau depends both on the presence of a large outward, repolarising current, carried by chloride and/or potassium ions, and on the presence of a slow inward calcium current large enough to depolarise the membrane as the chloride current deactivates.
mesh_terms: D000200:Action Potentials; D000818:Animals; D002118:Calcium / Q000502:physiology; D002463:Cell Membrane Permeability; D002712:Chlorides / Q000502:physiology; D003080:Cold Temperature; D004901:Erythrocebus patas; D005701:Galago; D000882:Haplorhini; D006321:Heart / Q000502:physiology*; D066298:In Vitro Techniques; D011188:Potassium / Q000502:physiology; D011443:Strepsirhini
chemical_list: D002712:Chlorides; D011188:Potassium; D002118:Calcium