Fig. 7.

NMDARs expressed in basal ganglia neurons show similar sensitivity to external Mg²⁺.A, I–V relation of glutamate-activated peak currents in Na⁺-rich external solution containing 100 μm Mg²⁺ in a nucleated patch isolated from a subthalamic nucleus neuron. Traces of glutamate-activated currents at membrane potentials varied from −100 mV to +40 mV in 20 mV steps are shown as inset. The continuous curverepresents a polynomial of the fifth order fit to the data points.B, Bar graph of the average rectification index,g_−60mV/g_+40mV, of the NMDAR-mediated current in the types of basal ganglia neurons investigated. All data are from nucleated patches. Na⁺-rich external solution (100 μm external Mg²⁺, 10 μm glycine, and 10 μm CNQX) in all experiments.