Action potential across cell membrane is maintained by?
Ans. a (Na+ K+ Pump).(Ref. Ganong, Physiology, 21st/pg.58) END PLATE POTENTIALACTION POTENTIAL1.Graded depolarization potential that developes at NMJ in skeletal and cardiac muscles but not in smooth muscles.Not a graded potential2.Is highly local event (confined to motor end plate), does not propagate.Propagates with no decrement with time3.Does not show ail or none phenomenon stronger stimulus causes greater EPP.Stimulus stronger than adequate, do not cause bigger AP.4.EPP is forerunner of APMaintained by Na+K+ ATPase pump.
Na+ K+ pump
cAMP
Ca++
Phosphodiesterase
General