Chronic Methylphenidate Alters Tonic and Phasic Glutamate Signaling in the Frontal Cortex of a Freely-Moving Rat Model of ADHD.

Chronic Methylphenidate Alters Tonic and Phasic Glutamate Signaling in the Frontal Cortex of a Freely-Moving Rat Model of ADHD. Neurochem Res. 2018 Feb 03;: Authors: Miller EM, Quintero JE, Pomerleau F, Huettl P, Gerhardt GA, Glaser PEA Abstract Glutamate dysfunction has been implicated in a number of substance of abuse studies, including cocaine and methamphetamine. Moreover, in attention-deficit/hyperactivity disorder (ADHD), it has been discovered that when the initiation of stimulant treatment occurs during adolescence, there is an increased risk of developing a substance use disorder later in life. The spontaneously hypertensive rat (SHR) serves as a phenotype for ADHD and studies have found increased cocaine self-administration in adult SHRs when treated with the stimulant methylphenidate (MPH) during adolescence. For this reason, we wanted to examine glutamate signaling in the pre-limbic frontal cortex, a region implicated in ADHD and drug addiction, in the SHR and its progenitor control strain, the Wistar Kyoto (WKY). We chronically implanted glutamate-selective microelectrode arrays (MEAs) into 8-week-old animals and treated with MPH (2 mg/kg, s.c.) for 11 days while measuring tonic and phasic extracellular glutamate concentrations. We observed that intermediate treatment with a clinically relevant dose of MPH increased tonic glutamate levels in the SHR but not the WKY compared to vehicle controls. After chronic treatment, ...
Source: Neurochemical Research - Category: Neuroscience Authors: Tags: Neurochem Res Source Type: research