PEMOLINE PRODUCES IPSILATERAL TURNING BEHAVIOR IN UNILATERAL 6-OHDA-LESIONED RATS

1. Male Sprague-Dawley rats received either a unilateral injection of 6-hydroxy-dopamine or vehicle injection into the medial forebrain bund le. 2. Two weeks post surgery, all rats received a pemoline challenge (250 mg/kg s.c.), and rotational and stereotyped behaviors were videot aped and analyzed. 3. All rats regardless of injection expressed stere otyped behaviors and hyper-locomotion after pemoline challenge. 4. Hig h performance liquid chromatography (HPLC) with electrochemical detect ion was used to evaluate changes in the levels of dopamine, serotonin and their metabolites in neostriata. 5. Rats with dopamine depleting l esions exhibited ipsilateral rotational behavior, indicating that pemo line, a central stimulant, is an indirect dopamine agonist in the rat. 6. The extent of dopamine depletion and serotonin elevation in the ne ostriatum in lesioned animals was related to the expression and degree of rotational behavior.