Which of the following cause an increase in ACh release from the presynaptic neuron?
Blocking calcium channels on presynaptic
Blocking chloride channel on presynaptic
Blocking Na channel
Blocking K channels
Ans. D. Blocking K channels* Potassium channel blocker will cause an increase in ACh release from the presynaptic neuron.* Blockade of presynaptic potassium channels promotes activation of voltage-gated calcium channels leading to the increased release of acetylcholine in the neuromuscular junction. Aminopyridines used in the treatment of Lambe-Eaton myasthenic syndrome acts by this mechanism and improves the muscle strength in the patients