Final answer:
Acetylcholine (ACh) is a neurotransmitter critical for synapse communication, which is released from presynaptic vesicles and binds to post-synaptic receptors to trigger a response. Reuptake is a process that helps clear ACh from the synaptic cleft by pumping it back into the neuron. Additionally, acetylcholinesterase can degrade ACh, influencing the neurotransmitter's levels in the synaptic cleft.
Step-by-step explanation:
The neurotransmitter acetylcholine (ACh) has a critical role in transmitting signals across the synapse. During neurotransmission, ACh, stored in presynaptic vesicles, is released into the synaptic cleft as a result of an action potential arriving at the presynaptic terminal. This release is triggered due to an influx of calcium ions allowing the vesicles to merge with the presynaptic membrane and pour their contents into the synaptic gap. The acetylcholine then binds to ACh receptors on the post-synaptic membrane, initiating depolarization and potentially an action potential in the subsequent neuron if the signal is strong enough.
After neurotransmission, reuptake is one of the processes that clear the neurotransmitter from the synapse. Reuptake involves the neurotransmitter being pumped back into the presynaptic neuron, clearing the synapse, which is crucial for the reset of the postsynaptic membrane and regulation of neurotransmitter production. In addition to reuptake, the enzyme acetylcholinesterase can react with ACh leading to its degradation, allowing the synapse to clear and reset. Some drugs target this process to increase the amount of acetylcholine in the synaptic cleft, which can, for example, help alleviate symptoms in patients with Alzheimer's by enhancing neurotransmission.