Pepeu_1978_Pharmacology_16 Suppl 1_204

The effect of bromocriptine on acetylcholine (ACh) output from the cerebral cortex was investigated in anaesthetized rats. Bromocriptine caused a brief decrease in ACh output at the dose of 0.1 mg/kg i.p. and a dose-related long-lasting increase at doses from 1.25 to 10 mg/kg i.p. Apomorphine elicited an increase in ACh output when injected intraperitoneally at doses from 0.1 to 10 mg/kg. When bromocriptine was administered to rats in which a septal lesion had been made 12 days prior to the test, no increase in ACh output was observed. Bromocriptine seems therefore to stimulate a cortical cholinergic pathway originating from or passing through the septum.