LEFT RIGHT NIGROSTRIATAL ASYMMETRY IN SUSCEPTIBILITY TO NEUROTOXIC DOPAMINE DEPLETION WITH 6-HYDROXYDOPAMINE IN RATS/

Male Sprague-Dawley rats were investigated for the existence of a left /right hemispheric population asymmetry in the extent of striatal dopa mine depletion following unilateral lesions with B-hydroxydopamine (6- OHDA) in the left or right substantia nigra. Four doses of 6-OHDA were employed (with left and right lesion groups at each dose). Analysis o f striatal dopamine depletion revealed significant main effects not on ly for dose of 6-OHDA, but also for side of lesion, with right-lesione d rats having greater dopamine depletion across doses. In a group of n on-lesioned rats, randomly selected from this population, striatal dop amine turnover showed a significant right-sided bias. It is suggested that the latter functional asymmetry may have been responsible for the neurotoxic depletion asymmetry seen in lesioned animals, and that sid e of lesion should be considered when attempting to produce consistent and maximal dopamine depletion in large scale studies with the unilat eral 6-OHDA lesion paradigm.