Table 3.

Effects of anticonvulsants on pHi of CA3 neurones

Drug	Slices	Neurones	Responses	pHi1	pHi (treatment)ΔpHi2(range)	ΔpHi2	ΔpHi2(mean±SD)	pH-active3
All	47	58	18 of 68	6.94 ± 0.14	6.92 ± 0.14	0.04–0.10	0.07 ± 0.02
Carbamazepine	6	6	50 µM: 1of 6	6.95 ± 0.14	6.93 ± 0.15	0.10	0.10	N
Clonazepam	6	6	50 µM: 0 of 6	7.01 ± 0.09	7.01 ± 0.09	<0.03	<0.03	N
Gabapentin	6	6	50 µM: 0 of 6	6.97 ± 0.10	6.97 ± 0.10	<0.03	<0.03	N
Lamotrigine	6	6	50 µM: 0 of 6	6.95 ± 0.08	6.95 ± 0.08	<0.03	<0.03	N
Tiagabine4	8	10	10 µM: 3 of 3	7.03 ± 0.15	6.97 ± 0.16*5	0.05–0.07	0.06 ± 0.01	Y
			50 µM: 11 of 11	6.95 ± 0.12	6.87 ± 0.12**	0.04–0.10	0.07 ± 0.02	Y
zonisamide	15	24	50 µM: 3 of 30	6.91 ± 0.17	6.90 ± 0.16	0.04–0.10	0.08 ± 0.04	N

¹Steady pHi prior to treatment (control condition).

²Responding cells only (ΔpHi > 0.03 pH units).

³Y = Yes, N = No.

⁴Only acidic deflections.

⁵Asterisks indicate significant differences from control.

^*P < 0.05;

^**P < 0.01.

pHi, intracellular pH; SD, standard deviation.