In vitro glutamate-stimulated release of dopamine from nucleus accumbens core and shell of spontaneously hypertensive rats

Abstract

Spontaneously hypertensive rats (SHR) are used as a model for attention-deficit hyperactivity disorder (ADHD) since SHR display the major symptoms of ADHD (hyperactivity, impulsivity, inablity to sustain attention during behavioral tasks). We previously showed that electrical and/or K+-stimulated release of dopamine (DA) from nerve terminals in the prefrontal cortex, nucleus accumbens, and caudate-putamen of SHR was significantly lower than that of Wistar-Kyoto (WKY) control rats. The aim of the present investigation was to determine whether glutamate-stimulated release of DA from nucleus accumbens core and shell of SHR was significantly different from that of WKY. Using an in vitro superfusion technique, we showed that glutamate-stimulated release of [3H]DA from striatal slices is mediated by glutamate activation of AMPA receptors and that glutamate-stimulated release of [3H]DA from nucleus accumbens core and shell of 4-6-week-old SHR and WKY is not significantly different. Glutamate-stimulated release of [3H]DA from SHR shell is significantly lower than SHR core and there is also a tendency for glutamate-stimulated [3H]DA release from SHR shell to be lower than release from WKY shell.