Figure 2.

Threshold electrical stimulation of area 35 often elicits CNQX- and AP-5-resistant IPSPs in vlEC neurons. A1, Response of a superficial vlEC neuron to area 35 stimuli of gradually increasing intensity (numbers on the right). A2, Response seen in A1 with 200 μA stimulus is not abolished by addition of CNQX and AP-5 to the aCSF. B, In many vlEC cells, IPSPs preceded EPSPs after threshold stimulation of area 35. B1, Example of IPSP–EPSP sequence evoked from area 35 at three different membrane potentials (numbers on the right), as determined by intracellular current injection. B2, The initial IPSP persisted after addition of CNQX and AP-5 to the aCSF. B3, CNQX- and AP-5-resistant IPSPs evoked in vlEC cells by threshold stimulation of area 35 reverse just below −70 mV (top) and are abolished by picrotoxin (bottom).