Visualisation of AMPA binding sites in the brain of mice lacking the adenosine A(2a) receptor

Adenosine A(2a) receptor knockout mice (A(2a)R k/o) have been characterised as hypertensive, aggressive, anxious and hypoalgesic [12]. Thus, the prese nt study was designed to investigate markers of glutamatergic transmission in specific brain nuclei associated with autonomic regulation. Visualisatio n of alpha-amino-3-hydroxy-5-methylisoxasole-4-propionic acid binding sites in the brains of A(2a)R k/o mice was achieved by utilising quantitative re ceptor autoradiography with (S)[H-3]-5-fluorowillardiine ([H-3]FW:10 nM) on slide-mounted sections of mouse-brain. [H-3]FW binding significantly incre ased in the nucleus tractus solitarius and area postrema of A(2a)R k/o mice compared with wildtype CD-1 mice. In other autonomic nuclei examined, bind ing was unchanged between wildtype and knockout mice. The present study sug gests that glutamatergic neurotransmission within certain neural pathways i nvolved in autonomic and motor control is altered in the brains of A(2a)R k /o mice. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved.