Question

which statement best describes the goal of medications used to treat myasthen gravis?
to increase the number of acetylcholine receptors
to decrease the number of synaptic vesicles
to promote multiple motor unit summation
to inhibit ca²+ release from the sarcoplasmic reticulum
to inhibit the function of cholinesterase

Explanation:

Myasthenia gravis is an autoimmune disorder where antibodies attack acetylcholine receptors. Cholinesterase inhibitors (like neostigmine) are used. Cholinesterase normally breaks down acetylcholine. By inhibiting cholinesterase, more acetylcholine is available to bind to the remaining receptors, improving neuromuscular transmission.

• Increasing acetylcholine receptors is not directly achieved by medications (immunosuppressants may help in reducing antibody - mediated destruction over time, but cholinesterase inhibitors work differently).
• Decreasing synaptic vesicles is not a goal.
• Promoting multiple motor unit summation is not the mechanism of these medications.
• Inhibiting \(Ca^{2 +}\) release is not relevant to the main mechanism of drugs for myasthenia gravis.

Answer:

To inhibit the function of cholinesterase.