Behavioural tests
Rotational Behavior After two weeks from surgery, rats were tested for apomorphine-induced rotational behavior (0.5 mg/kg s.c. over a period of 45 min). Only animals showing individual mean (2 full turns per min in the direction contralateral to the lesion side) were selected for the study (Padovan-Neto et al. 2009). Two days after that, chronic L-DOPA treatment was initiated.
L-DOPA-Induced dyskinesia Chronic L-DOPA treatment consisted of rats receiving a daily oral administration of L-DOPA for 14 days. Rats were monitored for LID using a rat dyskinesia scale (Anderson et al., 1999; Cenci and Lundblat, 2007; and modified by Padovan-Neto et al., 2009). Briefly, each rat was scored on a severity scale from 0 to 4 (where 0=absent, 1=occasional, 2=frequent, 3=continuous but interrupted by sensory distraction, and 4=continuous, severe and not suppressible) on each of the three axial, limb, and orofacial (ALO AIMs) subtypes (once every 20 min during 180 min after L-DOPA administration. Results are presented as the sum of ALO AIMs scores and analyzed as one item. Also, A dyskinesia time curve was generated by plotting the L-DOPA induced AIMs score against each monitoring time (20, 40, 60, 80, 100, 120, 140, 160, and 180 min) for an entire testing session. Animals with a L-DOPA induced. AIMs score of >10 and severity grading of >2 on at least one L-DOPA induced AIMs to score subtype were selected for the behavioral analysis (Lundblad et al., 2002; Winkler et al., 2002).