<prompt> The non depolarizing neuromuscular blocker has a normal activity with all the following except:MyotoniaMuscular dystrophyUpper motor neuron lesionsMyasthenia gravis  <response>: In myasthenia gravis circulating antibodies produce a functional reduction in the number of postsynaptic acetylcholine receptors. The myasthenia patients are usually resistant to Succinylcholine. Sensitively to non depolarizing NMB is increased to a variable extent. In Myasthenia patient nondepolarizing neuromuscular is given is less dose. 