ADORA2A and major depressive disorder: Because of an increasing evidence that adenosine neurotransmission is engaged in the development of psychiatric disorders, including major depressive disorder (Kaster et al. 2015; Ortiz et al. 2015; Ali-Sisto et al. 2016), and in the mechanisms underlying antidepressant effects (Deckert and Gleiter 1989; Fredholm et al. 1999; Cunha et al. 2008; Lara 2010; Gomes et al. 2011), while the number of prescribed drugs is growing (Murray and Lopez 1997; Tondo et al. 2003; Hashimoto 2011), the possible interaction between selective A2AR antagonist and commonly used antidepressants should be examined.