Cardiovascular System · NEET PG Preparation Physiology
During an experiment on isolated cardiac muscle, a researcher records an action potential with a prominent and prolonged plateau phase. Which ionic c…
Practice question from Cardiovascular System (NEET PG Preparation Physiology), with the correct answer and a step-by-step solution.
easy · MCQ · Q-B446D2
During an experiment on isolated cardiac muscle, a researcher records an action potential with a prominent and prolonged plateau phase. Which ionic current is primarily responsible for maintaining this plateau phase (Phase 2) in ventricular myocardial cells?
- A.Inward fast sodium current
- B.Inward L-type calcium currentCorrect answer
- C.Outward transient outward potassium current
- D.Outward inwardly rectifying potassium current
Solution
Phase 2 (the plateau phase) of the ventricular action potential is primarily maintained by the balanced inward movement of calcium through L-type calcium channels and outward movement of potassium through delayed rectifier potassium channels.
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