FETAL DOPAMINE NEURON TRANSPLANTS PREVENT BEHAVIORAL SUPERSENSITIVITY INDUCED BY REPEATED ADMINISTRATION OF L-DOPA IN THE RAT

We have studied in adult rats bearing a unilateral nigral lesion the effect of nigral grafts into the striatum on behavioral supersensitivity induced by chronic treatment of l-DOPA (100 mg/kg i.p.) plus benserazide (50 mg/kg i.p.). Repeated administration of l-DOPA increases contraversive circling. In rats without graft the contraversive circling was significantly increased after 8 and 14 daily injections of l-DOPA. On the other hand, the animals with transplants showed no such increase. Behavioral supersensitivity induced by repeated treatment of l-DOPA is often correlated with dyskinesia observed in the Parkinsonian patients. This suggests that the graft might be able to prevent this secondary effect. © 1990.