In vivo hydroxyl radical formation after quinolinic acid infusion into rat corpus striatum Article uri icon

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 (10mg/kg, i.p.) 60min before QUIN infusion. The mitochondrial toxin 3-nitropropionic 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 %26 Wilkins.

publication date

  • 2001-01-01