Figure 5.

Raising or decreasing [Ca²⁺]_o or the application of GABA_B receptor ligands affect uIPSCs. A, Action currents in a presynaptic NGFC (top trace) evoked uIPSCs (bottom traces), which were reduced by the GABA_B agonist baclofen (10 μm) in a reversible manner. B, In another cell pair, the amplitude of the uIPSCs was changed by decreasing or increasing [Ca²⁺]_o to 1 and 3.5 mm, respectively. The postsynaptic neurons were recorded at V_H = −50 mV with Cs-gluconate- (A) or K-gluconate- (B) based patch pipettes. C, Left graph, The histograms show the effects of CGP55845 (5 μm) and 3.5 mm extracellular Ca²⁺ on the uIPSCs normalized to control. Both agents increased the uIPSCs (p < 0.05; paired-t test; n = 10 and 4, respectively) to a similar extent (p > 0.05; unpaired t test). C, Right graph, The histograms illustrate the effects of baclofen and 1 mm extracellular Ca²⁺ on the uIPSCs normalized to control. Both agents decreased the uIPSCs (p < 0.05; paired-t test; n = 4 for both) to a similar extent (p > 0.05; unpaired t test). Each value represents a single experiment.