Presynaptic neurone
The presynaptic neurone is a neuron from the axon terminal of which an electrical impulse is transmitted across a synaptic cleft to the cell body or one or more dendrites of a postsynaptic neuron by the release of a chemical neurotransmitter; an example is acetylcholine[1].
When an action potential arrives at the axon terminal of the presynaptic membrane, Ca2+ ion channels open, allowing the ions to move into the cell down their concentration gradient. This, in turn, causes the neurotransmitter containing vesicles to translocate and fuse to the presynaptic membrane. The neurotransmitter diffuses across the synapse and starts a new action potential in the postsynaptic neurone[2].
Reference
1. <a href="https://medical-dictionary.thefreedictionary.com/presynaptic+neuron">presynaptic neuron</a>
- ↑ Anon, (2017). [online] Available at: https://medical-dictionary.thefreedictionary.com/presynaptic+neuron%7CAnon, (2017). [online] Available at: https://medical-dictionary.thefreedictionary.com/presynaptic+neuron]
- ↑ Purves D, Augustine GJ, Fitzpatrick D, et al., editors. Neuroscience. 2nd edition. Sunderland (MA): Sinauer Associates; 2001. Excitatory and Inhibitory Postsynaptic Potentials. Available from: https://www.ncbi.nlm.nih.gov/books/NBK11117/accessed 17/11/17