Abnormal involuntary movements (AIMs)
Two weeks after the 6-OHDA microinjection rats received a daily oral administration of L-DOPA for 14 days. The AIMs score was assessed by an experienced observer that was blinded to the treatment, according to a scale described by Anderson et al., (1999), Cenci and Lundblat, (2007) and modified by Padovan-Neto et al. (2009). The sum of the severity+amplitude score of the axial, limb, and orofacial AIMs for each monitored period is referred to as the global AIMs score or ALO AIMs (Anderson et al., 1999). AIMs were scored over a 1-min period every 20 min for a total of 180 min, post-L-DOPA administration. Each of the three subtypes was scored according to the severity scale, which ranges 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). In addition, the amplitude of the ALO AIMs, and L-DOPA induced AIMs score, was measured and ranged from 0 to 4 (the maximum amplitude of the L-DOPA induced AIMs score during the observation period. 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. We have created individual curves for each L-DOPA induced AIMs score category (limb, orofacial, and axial). Based on previous studies (Lundblad et al., 2002; Winkler et al., 2002), animals with an L-DOPA induced AIMs score of >10 and severity grading of >2 on at least one L-DOPA induced AIMs score subtype during treatment with L-DOPA, were selected for the behavioral analysis.