Figure 4.
The primary site of action of the GABABR antagonist is in the SGS. A1, A2, Schematic showing the arrangement of recording (Rec) and stimulating (Stim) electrodes and a puff pipette containing 1 mm CGP (CGP puff) on the SC slices. The puff pipette was placed either in the SGS (A1) or SGI (A2). B1, SGS stimulation evoked EPSC bursts in an SGI non-GABAergic neuron in the presence of gabazine (10 μm) (black trace). When CGP was puff applied locally into the SGS, the decay time of the EPSC bursts was greatly prolonged without changing peak amplitude (gray trace). B2, After recovery from these effects (black trace), puff application of CGP into the SGI induced almost no effect (gray trace). Membrane potential was held at −65 mV. C1, C2, Summary graphs showing the effects of local puff application of CGP into SGS (C1) or SGI (C2). *p < 0.05.