ACh esterase inhibition:.
1. A chemical that prevents the release of ACh from the presynaptic neuron.
2. A chemical that binds to a voltagegated K channels that prevents them from opening.
3. A chemical that binds to ligandgated receptors that prevents them from closing.

Acetylcholine

Explanation:

Acetylcholinesterase (AChE) is an enzyme that catalyzes the breakdown of acetylcholine and some other choline esters that function as neurotransmitters. It is found at mainly neuromuscular junctions and in chemical synapses of the cholinergic type, where its activity serves to terminate synaptic transmission. It belongs to carboxylesterase family of enzymes. It is the primary target of inhibition by organophosphorus compounds such as nerve agents and pesticides.

During neurotransmission, ACh is released from the presynaptic neuron into the synaptic cleft and binds to ACh receptors on the post-synaptic membrane, relaying the signal from the nerve. AChE, also located on the post-synaptic membrane, terminates the signal transmission by hydrolyzing ACh. The liberated choline is taken up again by the pre-synaptic neuron and ACh is synthesized by combining with acetyl-CoA through the action of choline acetyltransferase.

Option 1 is correct.

Explanation:

Just like in the option 1 which is the most correct option, Acetylcholinesterase inhibitor is an enzyme inhibitor which prevents the release of the neurotransmitter known as the acetylcholine(ACh) from the presynaptic neuron. Normally the acetylcholine(ACh) is further broken down into acetate and choline but with the inhibitor present the breaking down will not take place and thereby making more acetylcholine(ACh) to be present in the muscle cell.

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