The mechanism by which neostigmine improves contraction of myasthenic muscle involves: A. Repetitive binding of the acetylcholine molecules to the same receptors at the muscle endplate B. Diffusion of acetylcholine released from motor nerve endings to a wider area activating neighbouring receptors C. Activation of motor end-plate receptors by neostigmine molecules themselves D. All of the above

1 Answer

Answer :

D. All of the above

Related questions

Description : The mechanism by which neostigmine improves contraction of myasthenic muscle involves: A. Repetitive binding of the acetylcholine molecules to the same receptors at the muscle endplate B. Diffusion of ... Activation of motor end-plate receptors by neostigmine molecules themselves D. All of the above

Last Answer : D. All of the above

Description : Neostigmine is preferred over physostigmine for treating myasthenia gravis because: A. It is better absorbed orally B. It has longer duration of action C. It has additional direct agonistic action on nicotinic receptors at the muscle end plate D. It penetrates blood-brain barrier

Last Answer : C. It has additional direct agonistic action on nicotinic receptors at the muscle end plate

Description : Edrophonium is more suitable for differentiating myasthenic crisis from cholinergic crisis because of its: A. Shorter duration of action B. Longer duration of action C. Direct action on muscle end-plate D. Selective inhibition of true cholinesterase

Last Answer : A. Shorter duration of action

Description : Dantrolene sodium reduces skeletal muscle tone by: A. Reducing acetylcholine release from motor nerve endings B. Suppressing spinal polysynaptic reflexes C. Inhibiting the generation of muscle action potential D. Reducing Ca2+ release from sarcoplasmic reticulum in the muscle fibre

Last Answer : D. Reducing Ca2+ release from sarcoplasmic reticulum in the muscle fibre

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Last Answer : B. Generating α-methyl noradrenaline in brain which reduces sympathetic tone

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Description : Neostigmine is preferred over physostigmine for treating myasthenia gravis because: A. It is better absorbed orally B. It has longer duration of action C. It has additional direct agonistic action on nicotinic receptors at the muscle end plate D. It penetrates blood-brain barrier

Last Answer : C. It has additional direct agonistic action on nicotinic receptors at the muscle end plate

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Last Answer : acetylcholine

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