title: [Sodium currents in muscles incubated in potassium-free Ringer's solution. Effect of ouabain on unidirectional sodium currents].
abstract: Frog sartorius muscles subjected to loading with Na in K-free Ringer solution in the cold were subsequently labelled with 22Na. The uptake of 22Na is not sensitive to ouabain (10(-4) M) while sodium efflux is decreased by oubain. It is concluded that ouabain-sensitive Na-for Na interchange is not present in this condition. Possibly ouabain-sensitive sodium efflux is partly or completely potassium-requiring fraction since some K (approximately 10 microM) is inevitably present in K-free solution. The increase in the rate constant for potassium loss in the presence of ouabain favours this supposition.
mesh_terms: D000818:Animals; D001001:Anura; D002463:Cell Membrane Permeability / Q000187:drug effects; D009132:Muscles / Q000187:drug effects* / Q000378:metabolism; D010042:Ouabain / Q000494:pharmacology*; D011188:Potassium / Q000502:physiology*; D012964:Sodium / Q000378:metabolism*; D013696:Temperature
chemical_list: D010042:Ouabain; D012964:Sodium; D011188:Potassium
vernacular_title: Potoki natriia v myshtsakh, inkubirovannykh v beskalievom rastvore Ringera. Vliianie uabaina na odnonapravlennye potoki natriia.