Figure 3.

A subset of CA1 SO interneurons contain a pH and bupivacaine-sensitive current. A, Whole-cell voltage-clamp recording of a pH- and bupivacaine-sensitive neuron. The holding current became more positive after the pH was increased and returned to control levels after bupivacaine (20 μm) application (top). The input resistance decreased in pH 8.4, which was reversed after application of bupivacaine (bottom). B, Current–voltage relationship of the base (black) and bupivacaine (gray)-sensitive current. C, Example neurolucida drawing of a pH- and bupivacaine-sensitive cell. s.o., Stratum oriens; s.p., stratum pyramidale. D, Summary of the current–voltage relationship for the base-sensitive current. The GHK fit (dotted lines) has been shifted by 9 mV to account for the difference in reversal potentials. E, Summary of the effect of base and base plus bupivacaine (8.4+Bup) on holding current. E, F, Open gray circles and dotted lines represent individual cells, and filled black circles and solid lines represent the mean. F, Summary of the effect of pH on input resistance. Error bars equal SEM.