The following is the feature of depolarizing blockade?: (A) Tetanic fade, (B) Post tetanic potentiation, (C) Progression to dual blockade, (D) Antagonism by anticholinesterases
Answer is C. A depolarizingneuromuscular blocking agent is a form of neuromuscular blocker that depolarizes the motor end plate. Neuromuscular-blocking drugs block neuromuscular transmission at the neuromuscular junction, causing paralysis of the affected skeletal muscles. This is accomplished either by acting presynaptically the inhibition of acetylcholine (ACh) synthesis or release or by acting postsynaptically at the acetylcholine receptors of the motor nerve end-plate. While some drugs act presynaptically (such as botulinum toxinand tetanus toxin), those of current clinical impoance work postsynaptically.