There are many different neurotransmitters in the CNS, each binding to a specific receptor type which has a distinct distribution and role within the CNS.[Purves, Augustine & Fitzpatrick et al., 2008; Kandel, Schwartz & Jessell, 2000; Stahl, 2013] Some common neurotransmitters are listed in the table on this slide. Defects in many neurotransmitter pathways have been implicated in psychiatric disorders.
The variety of neurotransmitters that operate within the CNS adds to the functional complexity of the brain.[Purves, Augustine, Fitzpatrick et al., 2008] Different neurotransmitters can produce different responses on the same neurone; e.g., a neurone might be excited by serotonin but inhibited by the binding of GABA.[Purves, Augustine, Fitzpatrick et al., 2008]
Exactly what constitutes a neurotransmitter has been the subject of some disagreement but, generally, a neurotransmitter must:[Purves, Augustine, Fitzpatrick et al., 2008]
- be present within the presynaptic neurone
- be released in response to presynaptic depolarisation, and the release must be calcium-dependent
- have specific receptors on the postsynaptic neurone.
References:
Purves D, Augustine GJ, Fitzpatrick D, et al. (eds). Neuroscience. 4th Edition. Sinauer Associates, 2008.
Kandel ER, Schwartz JH, Jessell TM (eds). Principles of Neural Science. 4th Edition. McGraw-Hill, 2000. Stahl SM.
Stahl’s Essential Psychopharmacology. Neuroscientific Basis and Practical Applications. 4th Edition. © Cambridge University Press, 2013.
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