Simola Nicola, Fenu Sandro, Baraldi Pier G, Tabrizi Mojgan Aghazadeh, Morelli Micaela
Department of Toxicology and Centre of Excellence for Neurobiology of Dependence, University of Cagliari, 09124 Cagliari, Italy.
Exp Neurol. 2006 Nov;202(1):255-7. doi: 10.1016/j.expneurol.2006.05.015. Epub 2006 Jun 30.
An involvement of globus pallidus (GP) in the antiparkinsonian effects of A(2A) receptor antagonists has been proposed on the basis of the selective localization of A(2A) receptors on the striatopallidal pathway. In order to investigate this possibility, the present study evaluated rotational behavior in unilaterally 6-hydroxydopamine-lesioned rats following infusion of the water-soluble A(2A) receptor antagonist SCH BT2 into GP. SCH BT2 (5 microg/1 microl) altered neither motor behavior nor produced postural asymmetry by itself. However, when infused concomitantly with a parenteral subthreshold dose of l-DOPA (3 mg/kg i.p.) capable of inducing modest contralateral rotational behavior (34.7 +/- 20.7/1 h), SCH BT2 significantly potentiated the number of contraversive rotations (167.4 +/- 16.3/1 h). These results suggest that A(2A) receptors located in the globus pallidus may be involved in the antiparkinsonian effects of A(2A) antagonists.
