Fig. 3.

Dose–response properties of NMDA-activated currents in embryonic and postnatal CR cells. A–C,Representative traces obtained at different ages with various concentrations of NMDA applied for 3 sec, as indicated by thebars above the traces. D, Corresponding concentration–current density (I) data fit with an equation of the form: I =I_max[NMDA]^nH/(EC₅₀^nH+ [NMDA]^nH), where nH = Hill number. Parameter values are reported in Table 1. Theinset shows non-normalized data for E18 CR cells. Currents were recorded with CsCl pipettes at a holding potential of −60 mV. The extracellular medium was nominally Mg²⁺-free and contained 10 μmglycine.