Electric stimulation of the musculocutaneous nerve causes a rapid twitch of the biceps muscle. Electron microscopy shows numerous vesicles within the musculocutaneous nerve terminals. In order for these vesicles to release their contents into the synaptic cleft, which of the following substances is required?

Question

Quizplus · Accepted Answer

Eductional Objective: Acetylcholine release from presynaptic terminal vesicles at the neuromuscular junction depends upon the influx of extracellular calcium into the presynaptic terminal. Calcium influx into the nerve terminal occurs following neuronal depolarization and opening of voltage-gated calcium channels.

Electric Stimulation of the Musculocutaneous Nerve Causes a Rapid Twitch