Fig. 4.

Evoked responses are mediated by nicotinic, glutamatergic, and GABAergic receptors. A, In current-clamp mode, electrical stimulation (450 μA, 300 μsec) lateral to the SpL elicits an EPSP in an SpL neuron (first trace). When GABA_Areceptors are blocked with bicuculline, the identical stimulus produces an action potential (second trace). Further addition of DNQX blocks the action potential (third trace), and most of the remaining EPSP is blocked by subsequent DHβE application (last trace). B, After a 55 min washout of all the antagonists, the experiment was repeated in voltage-clamp mode.