Aberrant glutamate signaling in the prefrontal cortex and striatum of the spontaneously hypertensive rat model of attention-deficit/hyperactivity disorder

Rationale Attention-deficit/hyperactivity disorder (ADHD) is thought to involve hypofunctional catecholamine systems in the striatum, nucleus accumbens, and prefrontal cortex (PFC); however, recent clinical evidence has implicated glutamate dysfunction in the pathophysiology of ADHD. Recent studies show that increased stimulation of dopamine D2 and D4 receptors causes inhibition of N -methyl- d -aspartate and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors, respectively. The spontaneously hypertensive rat (SHR) model of ADHD combined type (C) has been found to have a hypofunctional dopamine system in the ventral striatum, nucleus accumbens, and PFC compared to the control Wistar Kyoto (WKY) strain. Objectives Based on the current understanding of typical dopamine–glutamate interactions, we hypothesized that the SHR model of ADHD would have a hyperfunctional glutamate system terminating in the striatum, nucleus accumbens, and PFC. Results High-speed amperometric recordings combined with four-channel microelectrode arrays to directly measure glutamate dynamics showed increased evoked glutamate release in the PFC (cingulate and infralimbic cortices, p