TY - JOUR T1 - Nigrostriatal Lesions Alter Oral Dyskinesia and c-Fos Expression Induced by the Serotonin Agonist 1-(<em>m</em>-Chlorophenyl)piperazine in Adult Rats JF - The Journal of Neuroscience JO - J. Neurosci. SP - 5170 LP - 5178 DO - 10.1523/JNEUROSCI.20-13-05170.2000 VL - 20 IS - 13 AU - Philippe De Deurwaerdère AU - Marie-Françoise Chesselet Y1 - 2000/07/01 UR - http://www.jneurosci.org/content/20/13/5170.abstract N2 - The loss of dopaminergic innervation of the basal ganglia, a group of subcortical regions involved in motor control, is the hallmark of Parkinson's disease. The resulting molecular and cellular alterations mediate behavioral deficits and may modify neuronal responses to other neurotransmitters. In the present study, we sought to determine the effects of chronic dopamine (DA) depletion on responses mediated by stimulation of serotonergic 2C (5-HT2C) receptors, a serotonergic receptor subtype present in discrete regions of the basal ganglia. Specifically, the effects of unilateral lesions of nigrostriatal DA neurons on oral dyskinesia and Fos protein expression induced by the non-selective 5-HT2C agonist 1-(m-chlorophenyl)piperazine (m-CPP) were examined.Confirming previous findings, both peripheral and local injections ofm-CPP into the subthalamic nucleus elicited oral dyskinesia. Nigrostriatal lesions markedly enhanced oral bouts induced by peripheral but not intrasubthalamic administration ofm-CPP. In intact rats, Fos expression was increased bym-CPP (1 mg/kg, i.p.) in the striatum and the subthalamic nucleus. After nigrostriatal lesions,m-CPP-induced Fos expression remained unchanged in the subthalamic nucleus but was reduced in the medial quadrants of the striatum and was markedly enhanced in the entopeduncular nucleus. These data demonstrate regionally specific alterations in behavioral and cellular responses to a serotonergic agonist in an animal model of Parkinson's disease. ER -