GluR1 and GluR2/3 subunits of the AMPA‐type glutamate receptor are associated with particular types of neurone in laminae I–III of the spinal dorsal horn of the rat

GluR1 and GluR2 subunits of the α‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazolepropionate (AMPA) receptor are expressed at high levels by neurones in laminae I–III of rat spinal dorsal horn, an area which contains numerous, densely packed small neurones. In order to determine whether these subunits are expressed by inhibitory or excitatory neurones, we combined pre‐embedding immunocytochemistry with antibodies that recognize either GluR1, or an epitope common to GluR2 and 3, with postembedding detection of γ‐aminobutyric acid (GABA) and glycine. Most (78%) of the neurones with GluR1‐immunoreactivity were GABA‐immunoreactive, and some of these were also glycine‐immunoreactive, whereas nearly all (97%) of the GluR2/3‐immunoreactive neurones were not GABA‐ or glycine‐immunoreactive.