Adenosine A2A receptors: localization and function

Adenosine is an endogenous purine nucleoside present in all mammalian tissues, that originates from the breakdown of ATP. By binding to its four receptor subtypes (A1, A2A, A2B, and A3), adenosine regulates several important physiological functions at both the central and peripheral levels. Therefore, ligands for the different adenosine receptors are attracting increasing attention as new potential drugs to be used in the treatment of several diseases. This chapter is aimed at providing an overview of adenosine metabolism, adenosine receptors localization and their signal transduction pathways. Particular attention will be paid to the biochemistry and pharmacology of A2A receptors, since antagonists of these receptors have emerged as promising new drugs for the treatment of Parkinson's disease. The interactions of A2A receptors with other nonadenosinergic receptors, and the effects of the pharmacological manipulation of A2A receptors on different body organs will be discussed, together with the usefulness of A2A receptor antagonists for the treatment of Parkinson's disease and the potential adverse effects of these drugs

A Questionnaire on Materialisms

Recent philosophical tendencies of “Actor-Network Theory,” “Object-Oriented Ontology,” and “Speculative Realism” have profoundly challenged the centrality of subjectivity in the humanities, and many artists and curators, particularly in the UK, Germany, and the United States, appear deeply influenced by this shift from epistemology to ontology. October editors asked artists, historians, and philosophers invested in these projects—from Graham Harman and Alexander R. Galloway to Armen Avanessian and Patricia Falguières to Ed Atkins and Amie Siegel—to explore what the rewards and risks of assigning agency to objects may be, and how, or if, such new materialisms can be productive for making and thinking about art today