Question

What does Pyridostigmine do at a mollecular and a cellular level, what are the mechanisms of action?

Answer 1

Ans .Pyridostigmine belongs to cholinterases  inhibitor class so it is inhibitory drug .It is used to increase muscle strength for symptomatic treatment of myasthenia gravis .It tends to break down the inhibition of acetylcholine and hence prolongs its effect like increase in intestinal and skeletal muscle ton , increase sweating and salivation .It also reverses non depolarizing neuromuscular blocking agents .Its mode of action is it inhibits acetylcholinesterase in synaptic cleft so cause slow down of acetylcholine hydrolysis .Carbamylate enzyme eventually regenerates by natural hydrolysis and excess ACh level revert to normal .ACh diffuse across the synaptic cleft and bind to the receptor on the post membrane and result in influex of Na + and hence depolarization occurs which leads to action potential .To prevent constant stimulation an enzyme acetylcholinesterase close the receptor on post synaptic membrane and hydrolysis ACh .