DOPAMINERGIC CONTROL OF THE SEPTAL-HIPPOCAMPAL CHOLINERGIC PATHWAY

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  • 1 January 1979
    • journal article
    • research article
    • Vol. 208  (3) , 476-479
Abstract
Apomorphine given s.c. was known to decrease the turnover rate of acetylcholine (TRACh) in the rat hippocampus. Blockade of dopaminergic receptors by intraseptal haloperidol or destruction of dopaminergic terminals by intraseptal 6-hydroxydopamine resulted in an increase in TRACh in the hippocampus. Specific destruction of the dopaminergic neurons projecting to the septum by the injection of 6-hydroxydopamine into the A10 mesencephalic cell group also resulted in an increased TRACh in the hippocampus. None of the above treatments affects TRACh in the cortex. It appears that dopaminergic neurons exert a tonic inhibitory effect on the ACh metabolism of the septal-hippocampal pathway, but do not affect that of cholinergic neurons projecting from the septum to the cortex. This decrease in the rate of metabolism may be associated with a regulation of the rate of neuronal firing.