Figure 3.

Pharmacological characterization of the prototypic afterdischarge in pyramidal cells. A, No effect of additional application of the nonspecific ionotropic glutamate receptor antagonist kynurenate (2 mm) and the metabotropic glutamate receptor antagonist MCPG (0.5 mm) on the expression of the prototypic afterdischarge in pyramidal cells (arrowheads). Action potentials are truncated for display. B, Complete abolishment of the expression of the prototypic afterdischarge by additional application of the GABA_A receptor antagonist bicuculline (25 μm). C, No effect of the GABA_B receptor antagonist CGP55845 (1 μm) on the prototypic afterdischarge expression (arrowheads). D, Abolishment of the prototypic afterdischarge expression by the gap junction blocker carbenoxolone (100 μm). E, Summary of the effects of these antagonists or the blocker on the expression of the prototypic afterdischarge in pyramidal cells. All of the pyramidal cells were recorded through the high Cl⁻ electrodes for reliable detection of the prototypic afterdischarge (see Fig. 2).