Microinjections of LSD (0.05 microgram), mescaline (0.5 microgram) and serotonin (10 microgram) into the medial raphe nucleus of rats resulted in a strong potentiation of apomorphine (1 mg/kg i.p.)-induced hypermotility. The potentiating effect of LSD or serotonin was suppressed by simultaneous injections of methysergide (0.05 microgram) or cyproheptadine (0.05 microgram) into the medial raphe...
The spontaneous locomotor activity of rats was investigated in an open-field test. Apomorphine and d,1-amphetamine caused a dose dependent increase of locomotor activity. LSD, mescaline, and DMT in low doses were ineffective, when given alone, but caused a strong potentiation of the hypermotility induced by apomorphine and d,1-amphetamine. Cyproheptadine antagonized the potentiating effect of...