CHARACTERIZATION OF EQUILIBRATIVE NUCLEOSIDE TRANSPORTER 1 (ENT1) IN FRONTOCORTICAL NERVE TERMINALS OF AN ANIMAL MODEL OF ADHD

Attention Deficit Hyperactivity Disorder (ADHD) is a neurodevelopmental condition with a high heritability. It can affect individuals of any age, although it is usually attributed to children and adolescents. The condition is characterized by a triad of symptoms: inattention, hyperactivity, and impulsivity. An imbalance in the dopaminergic transmission of the prefrontal cortex and striatum is one of the main causes of ADHD symptoms. Moreover, preclinical studies have shown that adenosine receptors normalize dopaminergic transmission and reduce cognitive impairments. Nevertheless, extracellular concentration of adenosine is also crucial for its signaling, as well as adenosine transporters, which are responsible for maintenance of adenosine levels. The equilibrative nucleoside transporter type 1 (ENT1) is the main regulator of adenosine extracellular levels in the CNS and its role has yet to be studied in ADHD.