Figure 4: Open Field test of Total Ambulatory and Central locomotor activity in RNU-/- and RNU-/+ after D-amphetamine sulfate administration. In order to assess any potential differences in the metabolism of the drug, D-amphetamine sulfate, and subsequent locomotor activity between RNU-/- and RNU-/+ rats, an Open Field test was conducted prior to surgery (i.e. prior to saline or 6-OHDA injection). We found no significant differences in overall ambulatory (A) during a 120-minute time interval. Error bars equal SEM (*, p=0.05).