Fig. 6.
Lack of effect on intrinsic excitability, presynaptic release or GABAA-R mechanisms. A–D: lack of effect on intrinsic excitability of CA1 pyramidal neurons tested by recording responses to intracellular current injection (representative traces in A). ZnCl2 (100 μM, 10–30 min, n = 8 each) had no effect on resting potential (B), action potential frequency (C), or input resistance (D). E and F: no significant effect of ZnCl2 (100 μM, 10 min) on paired-pulse ratios (PPR) of fEPSPs as determined from the ratio of the 2nd pulse (P2) to the 1st pluse (P1) (P = 0.50; n = 4). G: GABAA-R block by gabazine (10 μM) significantly increased SD propagation rate. The degree of SD acceleration by gabazine was unaffected by ZnCl2 (100 μM, 10 min; *P < 0.01; n = 4).