Ionic basis of action potential of autorrythmic cells
Phase 1: Pacemaker Potential:
Opening of voltage-gated Sodium channels called Funny
channels (If or f channels ).
Closure of voltage-gated Potassium channels.
Opening of Voltage-gated Transient-type Calcium (T-type Ca2+
channels) channels .
Phase 2: The Rising Phase or Depolarization:
Opening of Long-lasting voltage-gated Calcium channels
(L-type Ca2+ channels).
Large influx of Calcium.
Phase 3: The Falling Phase or Repolarization:
Opening of voltage-gated Potassium channels
Closing of L-type Ca channels.
Potassium Efflux.
