Alterations in dopamine signaling can lead to long-lasting neuronal adaptations that result in decreased or increased propensity for drug use. One of the proposed mechanism by which this can occur is dopamine transmission-induced alterations in the expression and subunit composition of AMPA receptors (Wolf, 2010). AMPA receptors are postsynaptic glutamate gated ion channels that mediate excitatory neurotransmission in the central nervous system. As such, AMPA receptors are core regulators of synaptic plasticity and activity-dependent remodeling of brain circuitries (Du et al., 2004; Haas et al., 2006). In a recent study by Saba et al. it was found that miR-181a expression in nucleus accumbens was increased by dopamine-mediated transmission and by the psychomotor stimulant drugs cocaine and amphetamines (Saba et al., 2012). Moreover, miR-181a was shown to repress GluA2-AMPA receptor subunit expression, and thereby modulate the magnitude of AMPA receptor clustering. Hence, miR-181a may be a key miRNA involved in drug-induced remodeling of the nucleus accumbens and greater striatal complex in response to drug exposure, thereby driving regulating the emergence of addiction. Recent evidence suggests that miRNAs also play a key
