<prompt> The drug that produces neuromuscular blockade by persistent depolarization is:D-tubocurarine.Gallamine.Pancuronium.Decamethonium.  <response>: Decamethonium is a peripherally acting skeletal muscle relaxant. It produces an immediate and rapid depolarization of the motor end plate. D-tubocurarine, pancuronium and gallamine are competitive antagonists of acetylcholine at the motor end plate and produce skeletal muscle relaxation. 