Low expression of GluR2 AMPA receptor subunit protein by human motor neurons

DISTURBANCE of glutamate neurotransmission may contribute to motor neuron i njury in amyotrophic lateral sclerosis. There is evidence that human motor neurons may express a specific profile of glutamate receptors, with low or absent expression of mRNA for the GluR2 AMPA receptor subunit, which has a crucial role in controlling calcium permeability. This study, using an immu nocytochemical approach with a GluR2 specific antibody, shows that human up per and lower motor neurons have a very low/absent expression of GluR2 prot ein, in contrast to many other neuronal groups. Thus, it is likely that hum an motor neurons express a high proportion of atypical, calcium permeable A MPA receptors which may contribute to selective vulnerability and may allow cell-specific modulation of the actions of glutamate. (C) 1999 Lippincott Williams & Wilkins.