Clinical sciences in medicine

Question 1

Three types of ANP

Answer 1

• Type A - released from the right atrium
• Type B - released from ventricles
• Type C - released from vascular endothelium

Question 2

Function of ANP

Answer 2

• Increased natriuresis
• Decreased vasoconstriction in response to stimuli
• Inhibition of renin and ADH
• Lowering of systolic BP

Question 3

What breaks down ANP?

Answer 3

• Neprilysin inhibitors
• This targets endopeptidase inhibitors which results in breakdown of ANP
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Question 4

Managment of treatment-refactory HF

Answer 4

Sacubitril/valsartan

Question 5

What is the resting membrane potential of a cardiac myocyte?

Answer 5

-90 mV

Question 6

five phases of the cardiac action potential?

Answer 6

• Phase 0 (Depolarization)
• Phase 1 (Initial Repolarization)
• Phase 2 (Plateau)
• Phase 3 (Rapid Repolarization)
• Phase 4 (Resting Membrane Potential)

Question 7

Phase 0

Answer 7

• Rapid depolarization due to the influx of Na+ ions through fast sodium channels.

Question 8

Phase 1 of the cardiac action potential

Answer 8

brief efflux of K+ ions through transient outward potassium channels.

Question 9

Phase 2 cardiac cycle

Answer 9

• Ca2+ ions enter the cell through L-type calcium channels
• balancing the K+ efflux and maintaining a prolonged depolarized state.
• sustains contraction of the cardiac muscle.

Question 10

Phase 3 cardiac cycle

Answer 10

• Rapid repolarization, where K+ efflux continues through delayed rectifier potassium channels,
• Ca2+ channels close, leading to the return of the membrane potential towards the resting level.

Question 11

Phase 4 cardiac cycle

Answer 11

• Resting membrane potential phase, maintained by the Na+/K+ ATPase pump
• inward rectifier potassium channels
• RP -90 mV.

Question 12

Inflow phase of cardiac cycle

Answer 12

• Rapid ventricular filling
• Rapid ventricular filling
• atrial contraction
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