Neuropharmacology And NeurotoxicologyIn vivo hydroxyl radical formation after quinolinic acid infusion into rat corpus striatumSantamaría, AbelCA; Jiménez-Capdeville, María E.1; Camacho, Alberto; Rodríguez-Martínez, Erika; Flores, Abigail; Galván-Arzate, SoniaAuthor Information Departamento de Neuroquímica, Instituto Nacional de Neurología y Neurocirugía Manuel Velasco Suárez, SSA. Av. Insurgentes Sur 3877, México D.F. 14269, Mexico; 1Departamento de Bioquímica, Facultad de Medicina, Universidad Autónoma de San Luis Potosí, Mexico CACorresponding author Received 31 May 2001; accepted 18 June 2001 Neuroreport: August 28, 2001 - Volume 12 - Issue 12 - p 2693-2696 Buy Abstract We studied the effect of an acute infusion of quinolinic acid (QUIN) on in vivo hydroxyl radical (.OH) formation in the striatum of awake rats. Using the microdialysis technique, the generation of .OH was assessed through electrochemical detection of the salicylate hydroxylation product 2,3-dihydroxybenzoic acid (2,3-DHBA). The .OH extracellular levels increased up to 30 times over basal levels after QUIN infusion (240 nmol/μl), returning to the baseline 2 h later. This response was attenuated, but not abolished, by pretreatment with the NMDA receptor antagonist MK-801 (10 mg/kg, i.p.) 60 min before QUIN infusion. The mitochondrial toxin 3-nitropropio nic acid (3-NPA, 500 nmol/μl) had stronger effects than QUIN on .OH generation, as well as on other markers of oxidative stress explored as potential consequences of .OH increased levels. These results support the hypothesis that early .OH generation contributes to the pattern of toxicity elicited by QUIN. The partial protection by MK-801 suggests that QUIN neurotoxicity is not completely explained through NMDA receptor overactivation, but it may also involve intrinsic QUIN oxidative properties. © 2001 Lippincott Williams & Wilkins, Inc.