Locomotor activity after repeated cocaine was measured similar to previously published reports58. Activity was monitored in rat sized cages with no bedding set up in a locomotor apparatus and evaluated on extent of ambulations in the x and y planes. On the first three days of each experiment the animals were given an intraperitoneal (i.p.) injection of normal saline and locomotor activity was monitored for 45 minutes. For each of the next five days animals were injected with i.p. cocaine (5 or 10 mg/kg) and their activity monitored for 45 minutes.
