The Unilateral Nigral Lesion Induces Dramatic Bilateral Modification on Rat Brain Monoamine Neurochemistry


Address for correspondence: Giuseppe Di Giovanni, Ph.D., Dipartimento di Medicina Sperimentale, Sezione di Fisiologia Umana, “G. Pagano,” Università degli Studi di Palermo, Corso Tuköry 129, 90134 Palermo, Italy. Voice: +39-0916555821; fax: +39-0916555823.


6-Hydroxydopamine (6-OHDA) is a neurotoxic compound commonly used to induce dopamine (DA) depletion in the nigrostriatal system, mimicking Parkinson's disease (PD) in animals. The aim of the present study was to evaluate the 7-day effect of unilateral nigral lesion on rat brain monoamine neurochemistry. Five brain regions were examined: the brain stem, cerebellum, hippocampus, striatum, and cortex. 6-OHDA-unilateral lesion dramatically modified DA, serotonin (5-HT) and their metabolites contents in both sides of the different brain nuclei. Furthermore, unilateral 6-OHDA lesion reduced DA and 5-HT contents and produced a robust inversion of their turnover in the nonlesioned side compared to sham-operated rats. These data suggest that 6-OHDA unilateral nigral lesion produces bilateral monoamine level modifications, and this piece of evidence should be taken into account when one interprets data from animal models of unilateral PD.