Acute unilateral sensorimotor cortex injury in the rat blocks d-amphetamine induced norepinephrine release in cerebellum

Pharmacologic studies have implicated norepinephrine in amphetamine-facilitated motor recovery following sensorimotor cortex injury in rats. We studied the acute effects of unilateral sensorimotor cortex ablation on the release of norepinephrine in cerebellum with in vivo dialysis. In rats without a cortex lesion, the administration of a single dose of d-amphetamine (2.6 mg/kg base weight, i.p.) resulted in a substantial increase in dialyzable norepinephrine in cerebellum reaching its peak 30 –40 min later (∼ 14 pg/μl, not corrected for recovery). The administration of the same dose of d-amphetamine to rats 60 min following a suction-ablation lesion of the right sensorimotor cortex did not result in norepinephrine release into the cerebellar dialysates. These data provide evidence for an acute remote effect of sensorimotor cortex injury on amphetamine-induced norepinephrine release in the cerebellum (diaschisis).