A developmental expression of AMPA-selective glutamate receptor subunits in human basal ganglia

The development of AMPA-selective glutamate receptors (GluR1 and GluR2–3) in human basal ganglia (BG) was investigated in 23 normal brains by means of an immunohistochemical method. Immunoreactivity to GluR1 and 2–3 was detected in the cytoplasm and dendrites of small and large neurons in the BG. GluR2–3 immunoreactivity-positive neurons were clearly observed at 23–24 gestational weeks (GW) in the globus pallidus and at 32 GW in the neostriatum, and reacted a peak at 32 GW and 39 GW, respectivelt. GluR2–3 positive neurons in the BG began to decrease at 1–4 months of age, reaching the low level of adults by 7 months of age. The developmental pattern of GluR1 was similar to that of GluR2–3 in the BG, but the immunoreactivity to GluR1 was a little weaker than that of GluR2–3 in the neostriatum. Furthermore, GluR1 and 2–3 subunit Western blotting confirmed the specificity of the immunohistochemistry. Our results suggest that the development of GluR1 and 2–3 in the BG is consistent with neuronal development in the BG, which supports further that GluR1 and 2–3 play an important role in neuronal differentiation and maturation of the BG.