NMDA glutamate receptors (NMDARs) in subthalamic nucleus cells are of potential importance in changes in the behaviour of the basal ganglia circuitry that occur in Parkinson’s disease and are therefore potential therapeutic targets (Hallett & Standaert, 2004). We have used patch-clamp recording methods to investigate the subtypes of NMDAR present in outside-out membrane patches from subthalamic nucleus cells in 300 um coronal brain slices from humanely killed 7 days old rats. Single channel recordings of NMDAR channels activated by 200 uM NMDA and 10 uM glycine were made. Distributions of channel amplitudes identified four conductance levels (19 ± 1.1, 41 ± 2.0, 52 ± 1.5 and 67 ± 1.0 pS). The presence of the two lower conductance states indicates that NR2D or NR2C subunits contribute to these receptors (Cull-Candy et al., 2001) while unusually large conductance openings (67 pS) were also observed in 3 out of 6 patches. The NR2B antagonist, ifenprodil (10 uM) reduced channel open probability by 62.6 ± 12.5% (mean ± S.E., n = 6 patches) confirming the presence of NR2B receptors. These data suggest that functional NMDARs in subthalamic nucleus in 1 week old rats are heterogeneous and include both low and high conductance receptors.