Figure 7.

Pressure application of glutamate to stratum moleculare evokes l-AP-4-sensitive GABAergic currents in principal cells. A, Diagram showing the location of the patch and puff pipette. Glutamate was applied by pressure from a pipette positioned into stratum moleculare, in the presence of DNQX (20 μm). Individual traces obtained in control, in the presence of l-AP-4, after washing l-AP-4, and in the presence of bicuculline (Bic; 20 μm) before and after (arrows) application of glutamate. B, Same as A, but the puff pipette was positioned close to the hilus. Note that, in this case, glutamate-evoked GABAergic currents were poorly affected by l-AP-4. Mean frequency (C) and amplitude (D) values of GABAergic currents (normalized to pre-glutamate values) evoked by pressure application of glutamate to stratum moleculare (white; n = 6) or to the hilus (black; n = 3).