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Multiple Choice

Which of the following inhibits Na/K-ATPase, potentially leading to hyperkalemia?

The correct choice involves agents that specifically inhibit Na/K-ATPase activity, leading to increased potassium levels in the serum, or hyperkalemia. Succinylcholine, a depolarizing neuromuscular blocker, can increase extracellular potassium levels through its mechanism of action. When succinylcholine binds to the acetylcholine receptor at the neuromuscular junction, it causes a persistent depolarization of the muscle membrane. This increased activity can lead to a temporary influx of potassium ions out of the cells, resulting in hyperkalemia. Additionally, beta-blockers can impair cellular uptake of potassium by blocking beta-adrenergic receptor-mediated stimulation of the Na/K-ATPase pump, which normally helps move potassium into cells. This dual mechanism involving succinylcholine and beta-blockers contributes to the potential for hyperkalemia. In contrast, the other choices contain agents that either do not inhibit Na/K-ATPase or do not have a significant effect on potassium homeostasis in the same manner. For example, albuterol and insulin promote the activity of Na/K-ATPase, thus driving potassium into cells and reducing serum potassium levels. Acetylcholine and norepinephrine primarily act on their respective receptors to mediate

The correct choice involves agents that specifically inhibit Na/K-ATPase activity, leading to increased potassium levels in the serum, or hyperkalemia. Succinylcholine, a depolarizing neuromuscular blocker, can increase extracellular potassium levels through its mechanism of action. When succinylcholine binds to the acetylcholine receptor at the neuromuscular junction, it causes a persistent depolarization of the muscle membrane. This increased activity can lead to a temporary influx of potassium ions out of the cells, resulting in hyperkalemia.

Additionally, beta-blockers can impair cellular uptake of potassium by blocking beta-adrenergic receptor-mediated stimulation of the Na/K-ATPase pump, which normally helps move potassium into cells. This dual mechanism involving succinylcholine and beta-blockers contributes to the potential for hyperkalemia.

In contrast, the other choices contain agents that either do not inhibit Na/K-ATPase or do not have a significant effect on potassium homeostasis in the same manner. For example, albuterol and insulin promote the activity of Na/K-ATPase, thus driving potassium into cells and reducing serum potassium levels. Acetylcholine and norepinephrine primarily act on their respective receptors to mediate