What characteristics are associated with Eaton-Lambert syndrome?

Eaton-Lambert syndrome, also known as Lambert-Eaton Myasthenic Syndrome (LEMS), is characterized primarily by a condition in which there is an impairment in the release of acetylcholine from nerve endings. This is often due to autoantibodies that target voltage-gated calcium channels on the presynaptic membrane at the neuromuscular junction.

The correct choice reflects the fact that patients with Eaton-Lambert syndrome often experience improved muscle strength with activity. This phenomenon occurs because muscle activity can lead to a temporary increase in calcium influx into the nerve terminal, partially compensating for the impaired release of acetylcholine. As the muscle is stimulated and used, this increased demand can result in greater release of acetylcholine up to the limited threshold, thereby enhancing muscle contraction and strength, albeit temporarily.

The others mentioned, such as sensitivity to muscle relaxants and a positive response to anticholinesterase agents, are not typical characteristics of Eaton-Lambert syndrome. In fact, patients generally do not show the same beneficial response to anticholinesterase treatment as seen in myasthenia gravis, and they may be less sensitive to non-depolarizing muscle relaxants due to their unique neuromus