[Effects of sodium and calcium ions on the potentials of cardiac pacemaker cells in the frog].
True and latent pacemaker cells were differentiated in the frog heart sino-atrial area. Within the first 5 min in the hyposodium solution, a decrease of the overshoot and maximal velocity of depolarization occurred. The true pacemaker cells did not reveal any changes of the AP parameters within 30-60 min. The cells of true pacemaker exhibited a higher sensitivity to the hypocalcium solution. The data obtained suggested a scheme of the whole cycle of Na+, K+ and Ca2+ exchange.
D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D002118:Calcium / Q000494:pharmacology*; D066298:In Vitro Techniques; D011896:Rana temporaria; D012849:Sinoatrial Node / Q000166:cytology / Q000187:drug effects*; D012964:Sodium / Q000494:pharmacology*
D012964:Sodium; D002118:Calcium
Effekty ionov natriia i kal'tsiia na potentsialy kletok voditelia ritma serdtsa liagushki.