There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.
Abstract
To investigate the influence of neurotransmitter on G-protein-coupled receptor trafficking
and compartimentalization in neurons, we have developed a model of primary neuronal
cultures from fetal rat striatum on which we have studied the cellular and subcellular
distribution and trafficking of the D(1) dopaminergic receptor. This receptor is known
to be somatodendritic and axonal targeted in vivo, mostly to extrasynaptic locations.
Immunohistochemical studies at the light and electron microscopic levels showed that,
in cultures, the D(1) dopaminergic receptor is expressed in the absence of dopamine
stimulation. The pattern of D(1) dopaminergic receptor immunostaining after stimulation
by the D(1) dopaminergic receptor agonist SKF 82958 (1 microM) is dramatically modified
with a decrease of the number of labeled D(1) dopaminergic receptor puncta (-40%)
and an increase of their size in both dendrites (+120%) and axons (+240%). Seven hours
after removal of the agonist, return to normal pattern was observed. The D(1) dopaminergic
receptor antagonist SCH 23390 (2 microM) abolishes the effect of SKF 82958. Electron
microscopy demonstrated, in dendrites, a translocation of the labeling from the plasma
membrane to endosomes. Axonal D(1) dopaminergic receptor redistribution after acute
stimulation indicates that the D(1) dopaminergic receptor is membrane targeted and
responsive to stimulation. These results validate primary culture of striatal neurons
to study subcellular localization and intraneuronal trafficking of G-protein-coupled
receptors. This preparation will be useful to address various questions concerning
the behavior and the trafficking of these receptors in neurons in relation to the
neurotransmitter environment.