Fig. 9. Functional expression of receptor-operated channels during early neuronal development. GABA (A) as well as glycine (B) evoked fast-activating and inactivating inward currents (HP -80 mV) in bipolar strong EGFP-positive cells. Co-application of the selective antagonists Bicuculline (A) and Strychnine (B) almost completely inhibited the activation of GABA- and glycine-evoked inward currents, respectively. The ionic nature was determined by performing ramp depolarizations (from -100 mV to 50 mV in 150 milliseconds) in the presence and absence of the agonist yielding a reversal potential of -27 mV, as expected for a Cl^- current (see inset in A).