The effects of p-chlorophenylalanine, reserpine, methysergide and cyproheptadine on the dopa-induced EEG synchronization in the rat.

The actions of drugs interfering with central indolaminergic mechanisms were assessed on the Dopa-induced EEG synchronization in the rat. The increased slow wave activity observed during the first 30 min following Dopa (100 mg/kg) was significantly decreased by p-chlorophenylalanine (400 mg/kg), reserpine (4 and 8 mg/kg) and methysergide (16 mg/kg). Cyproheptadine was ineffective in this respect. Our findings lend support to the hypothesis that the initial synchronization after Dopa is related to the release of 5-hydroxytryptamine.