A person experiences persistent muscle rigidity after prolonged exposure to an organophosphate pesticide. Which mechanism explains this effect on neuromuscular junctions?

💡 Explanation

Organophosphates inhibit acetylcholinesterase, which is crucial for breaking down acetylcholine in the synaptic cleft; because acetylcholinesterase inhibition increases acetylcholine concentration, it leads to continuous muscle stimulation and rigidity. Therefore, enzyme inhibition explains the persistent muscle rigidity, rather than increased receptor synthesis or altered neurotransmitter release.

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