KROK 1 2010 – Question 130 · KROK (Medicine) · Physiology
Vagus branches that innervate heart are being stimulated during an experiment. This caused reduction of heart rate due to the intensification of the following process (through the cell membrane of cardiac pacemaker):
- A. Potassium ion entry
- B. Calcium ion yield
- C. Potassium ion yield
- D. Calcium ion entry
- E. Calcium and potassium ion yield
Hint
Acetylcholine acts on muscarinic receptors of the pacemaker cells; ask which membrane current makes the resting potential more negative and slows spontaneous diastolic depolarisation.
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