Amino acid transmitters in the mammalian central nervous system

Amino Acid Transmitters in the Mammalian Central Nervous System 165
the activity of neurones throughout the mammalian central nervous system. The
evidence presented suggests that these substances deserve consideration as major
central transmitters involved with the relay of afferent information from the
spinal to the cortical level, the control of cerebral pyramidal and cerebellar
Purkinje cells, and of other cortical, subcortical and spinal neurones. The case
could even be argued that other substances such as acetylcholine, noradrenaline,
dopamine and 5-hydroxytryptamine, widely acknowledged as central transmitters,
are of relatively minor but nonetheless vital importance, being associated with
the finer control of functions such as movement, mood and behaviour. Due
consideration is thus required of amino acids and the "amines" when attempting
to understand the "magic loom" of synaptic interconnections that constitutes
the central nervous system.
With further elucidation and appreciation of the essential role of amino acids
as transmitters, and of disturbances of CNS function resulting from abnormalities
at the synaptic level, increasing opportunities will arise for therapeutic measures
based on chemical manipulation of the synthesis, storage, release, postsynaptic
action or inactivation of particular amino acids.
Acknowledgement. The authors are indebted to Mrs. R. MACLACHLAN, Mrs. P. SEARLE, Mrs. A. STE-
PHANSON, and particularly Mrs. H. WALSr~ for invaluable assistance in preparing this manuscript,
and are grateful for material provided prior to publication by colleagues in North America, Europe
and Japan.
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