Pharmacology Cardiovascular System Drugs 3

Question 1

Loop diuretics such as furosemide act on which segment of the nephron?

Accepted Answer

Thick ascending limb of the Loop of Henle

Answer

Furosemide inhibits the Na-K-2Cl cotransporter (NKCC2) in the thick ascending limb of the Loop of Henle, producing potent diuresis.

Question 2

Which statin is considered most potent and is also a substrate of OATP1B1, making it susceptible to drug interactions with cyclosporine?

Accepted Answer

Rosuvastatin

Answer

Rosuvastatin is among the most potent statins and is transported into hepatocytes by OATP1B1; cyclosporine inhibits this transporter, raising rosuvastatin plasma levels.

Question 3

Digoxin toxicity is potentiated by hypokalemia because:

Accepted Answer

Potassium and digoxin compete for the same binding site on Na/K-ATPase

Answer

Potassium and digoxin compete for the same binding site on the Na/K-ATPase; low potassium means less competition and enhanced digoxin binding and toxicity.

Question 4

Sacubitril/valsartan (Entresto) improves heart failure outcomes by combining an ARB with an inhibitor of which enzyme?

Accepted Answer

Neprilysin

Answer

Sacubitril inhibits neprilysin, which normally breaks down natriuretic peptides; blocking it raises BNP/ANP levels, promoting vasodilation and natriuresis.

Question 5

Which antiarrhythmic is the first-line IV agent for terminating paroxysmal supraventricular tachycardia (PSVT) due to AV nodal re-entry?

Accepted Answer

Adenosine

Answer

Adenosine transiently blocks AV nodal conduction by activating A1 receptors, interrupting re-entrant circuits that sustain PSVT.

Pharmacology Practice Test

Pharmacology Practice Test

Pharmacology Cardiovascular System Drugs 3