The role of striatal dopaminergic mechanisms in rotational behavior induced by phencyclidine and phencyclidine-like drugs.
Psychopharmacology January 1, 1998 A Mele, K M Wozniak, F S Hall et al.
Five drugs similar to phencyclidine (PCP) were tested in rats with brain lesions to see if they cause circling behavior and alter dopamine levels in the striatum. All five drugs caused the rats to turn in circles toward the side of the lesion, which typically indicates increased dopamine on the intact side. But measurements of dopamine in the striatum did not match this expectation. Only PCP itself increased dopamine levels. MK-801 caused strong circling but no dopamine increase. Dexoxadrol also caused circling without raising dopamine. TCP and SKF 10,047 raised dopamine only slightly (16% and 12%) at their peak. The authors conclude these drugs likely act through NMDA receptor blockade rather than by altering dopamine.