Mode of action of adenosine A2A receptor antagonists as symptomatic treatment for Parkinson's disease.

Adenosine A2A receptor antagonists are classified to be a recent new therapeutic strategy for the symptomatic treatment of Parkinson's disease, a hypokinetic movement disorder. First, this chapter addresses how adenosine A2A receptors are involved with brain motor control via the basal ganglia-thalamocortical circuit, considering anatomical and ultrastructural localization of the receptor in critical areas/neurons of the circuit. Then, based on the understanding of the functional significance of the receptor in the circuit, the mode of action of adenosine A2A receptor antagonists is explained by dynamism of the circuit and possible cellular mechanisms, highlighting the importance of the pathophysiological difference proposed between normal and disease state.