|
Copyright © 1998 by Institute of Pharmacology Polish Academy of Sciences |
Pol. J. Pharmacol., 1998, 50, 299-305 ISSN 1230-6002 |
|
N6-2-(4-aminophenyl)ethyladenosine (APNEA), a putative adenosine A3 receptor agonist, enhances methamphetamine-induced dopamine outflow in rat striatum.
K. GOŁEMBIOWSKA, A. ŻYLEWSKA. Pol. J. Pharmacol., 1998, 50, 299-305. In the present study, the effect of adenosine A3 receptor agonist, N6-2-(4-aminophenyl)ethyladenosine (APNEA), on methamphetamine (MTH)-induced dopamine (DA) release in rat striatum was evaluated using microdialysis in freely moving animals. MTH at a dose of 5 mg/kg injected 3-times every two hours produced massive overflow of DA and decline in the level of DOPAC (3,4-dihydroxyphenylacetic acid) and HVA (homovanillic acid). APNEA perfused locally to the striatum via microdialysis probe triggered opposite effects, at 75 µM it diminished MTH-induced DA overflow during first 2 h of the experiment (p < 0.05), but potently enhanced it at higher 100 µM concentration for entire period of treatment (p < 0.001). Concomitant release of glutamate in striatum was slightly decreased by MTH alone, and significantly diminished by coadministration of 100 µM APNEA (p < 0.001). The data indicate that activation of adenosine A3 receptor exerts rather toxic effect on DA neurons and exacerbates neurotoxicity of MTH. In addition, MTH-induced DA overflow does not seem to result from the increased release of striatal glutamate level. Key words: adenosine A3 receptor, DA and glutamate release, rat striatum, microdialysis, methamphetamine |
| Back to: Top | PJP - Home Page | |