![]() |
|
|
SJ O'Dell, FB Weihmuller, RJ McPherson and JF Marshall
Department of Psychobiology, University of California, Irvine.
Repeated administration of methamphetamine (m-AMPH) produces a prolonged elevation of extracellular dopamine (DA) levels in rat striatum and subsequent damage to striatal DA terminals. In the present study, a unilateral striatal infusion of quinolinic acid (QA) (15 ug/0.5 microliter) 2 weeks before repeated m-AMPH treatment (four injections of 4 mg/kg, s.c., at 2-hr intervals) protected that striatum from m-AMPH-induced DA terminal injury. One week after m-AMPH treatments, striatal DA contents were substantially below control values in the vehicle-infused striata, whereas the DA contents of the QA-infused striata were equal to those of animals not exposed to m- AMPH. The QA infusions alone injured striatal neurons, as indicated by decreased [3H]SCH 23390 and [3H]spiroperidol binding to D1 and D2 receptors, respectively. However, QA infusions by themselves did not significantly change the DA content or [3H]mazindol binding to the high- affinity DA transporter of the infused striata 3 weeks later. In vivo microdialysis was performed in the previously QA- or vehicle-infused striata during regimens of repeated m-AMPH or saline treatments. QA infusions that were effective in protecting against m-AMPH neurotoxicity did not significantly reduce stimulant-induced DA overflow, compared with the overflow that occurred in the vehicle- infused striata of m-AMPH-treated rats. Thus m-AMPH-induced DA overflow appears to be dissociated from the resulting DA terminal injury in the QA-infused striatum.(ABSTRACT TRUNCATED AT 250 WORDS)
This article has been cited by other articles:
![]() |
R. R. Metzger, H. M. Haughey, D. G. Wilkins, J. W. Gibb, G. R. Hanson, and A. E. Fleckenstein Methamphetamine-Induced Rapid Decrease in Dopamine Transporter Function: Role of Dopamine and Hyperthermia J. Pharmacol. Exp. Ther., December 1, 2000; 295(3): 1077 - 1085. [Abstract] [Full Text] |
||||
![]() |
K. B. Burrows, W. L. Nixdorf, and B. K. Yamamoto Central Administration of Methamphetamine Synergizes with Metabolic Inhibition to Deplete Striatal Monoamines J. Pharmacol. Exp. Ther., March 1, 2000; 292(3): 853 - 860. [Abstract] [Full Text] |
||||
![]() |
D. S. Reynolds, R. J. Carter, and A. J. Morton Dopamine Modulates the Susceptibility of Striatal Neurons to 3-Nitropropionic Acid in the Rat Model of Huntington's Disease J. Neurosci., December 1, 1998; 18(23): 10116 - 10127. [Abstract] [Full Text] [PDF] |
||||