CV 2: Cardiac Cell Electrophysiology
Atrium and Ventricles APs
SAN & AVN APs
MP and APs (General)
Phase 0: Upstroke
Phase 1: Early repolarization
Phase 2: Plateau
Phase 3: Repolarisation
Phase 4: Resting
Na Influx
Na close
Transient outward K+
L-type Ca channels
Delayed Rectifier K+ Channels
Rapidly activating
Slowly activating
Inward Rectifying K+ Channels
Pumps
3Na: 2K pump
3Na:1Ca2+ pump
ATP-driven Ca2+ pump
Slow and small Upstroke
L-Type Ca 2+
No early repolarization
No plateau
L-type Ca2+ are already closed
No transient K+ channels
No resting potential
Diastolic depolarization
Hyperpolarization-activated inward current channels
Depolarization from Na-Ca exchanger
T-type Ca2+ channels
ANS
Sympathetic
Parasympathetic
increase activity
Decrease activity via acetylcholine regulated K+ channels