Which muscle relaxant inhibits the reuptake of norepinephrine by the adrenergic nerves?

Which muscle relaxant inhibits the reuptake of norepinephrine by the adrenergic nerves?

• A. Pancuronium
• B. Pipecuronium
• C. Rocuronium
• D. Doxacurium

Answer: (A)

Pancuronium stands out because, in addition to blocking nicotinic receptors at the neuromuscular junction, it has a notable autonomic effect: it inhibits the reuptake of norepinephrine by adrenergic nerve terminals. This means norepinephrine stays in the synaptic cleft longer, boosting sympathetic stimulation of the heart (beta-1 receptors) and often producing tachycardia and sometimes hypertension. The other commonly used nondepolarizing relaxants don’t share this property to the same extent, so they don’t cause this particular autonomic effect.

Pancuronium stands out because, in addition to blocking nicotinic receptors at the neuromuscular junction, it has a notable autonomic effect: it inhibits the reuptake of norepinephrine by adrenergic nerve terminals. This means norepinephrine stays in the synaptic cleft longer, boosting sympathetic stimulation of the heart (beta-1 receptors) and often producing tachycardia and sometimes hypertension. The other commonly used nondepolarizing relaxants don’t share this property to the same extent, so they don’t cause this particular autonomic effect.