Summary
Cats were used for microelectrode recording from single cells in the amygdaloid complex, and for fluorescence histochemical demonstration of monoamines. It was found that the firing rate of amygdaloid neurones decreased sharply following the administration of 5-HTP, the precursor of serotonin. Conversely, it increased after the administration of L-DOPA, the precursor of dopamine and norepinephrine. The fluorescence microscopy studies, after formaldehyde condensation, showed the presence of what appear to be axosomatic synapses containing serotonin on amygdaloid and hippocampal neurones. We conclude that serotonin may be an inhibitory synaptic transmitter in these limbic structures.
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Supported by USPHS Grant NB-3496, General Research Support Grant FR-5575, USPHS Career Development Award NB-K3-15.437, and a grant from the Epilepsy Foundation.
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Eidelberg, E., Goldstein, G.P. & Deza, L. Evidence for serotonin as a possible inhibitory transmitter in some limbic structures. Exp Brain Res 4, 73–80 (1967). https://doi.org/10.1007/BF00235218
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DOI: https://doi.org/10.1007/BF00235218