Figure 3. A single in vivo administration of nicotine reduces LTP_GABA 2 hours after exposure, but not at 24 hours.

A, Single experiment illustrating LTP_GABA induced by bath application of SNAP onto a brain slice prepared 24 hours after saline-injection. Insets, Representative IPSCs evoked before (Control) and 15 min after (SNAP) drug application. B, Single experiment illustrating that LTP_GABA is unaffected in a slice prepared 24 hours after nicotine-injection. C, At 24 hours after exposure, averaged experiments show no significant difference in SNAP-induced potentiation of IPSCs from saline (n = 11) or nicotine-treated animals (n = 13). Statistical analysis revealed a significant effect of time (F_1,39 = 8.44, p < 0.001), but no significant effects of drug treatment (F_1,39 = 3.55, p > 0.05) or interaction between the two factors (F_1,39 = 0.36, p > 0.05). D, Single experiment illustrating LTP_GABA induced by bath application of SNAP onto a brain slice prepared 2 hours after saline-injection. E, Single experiment illustrating that LTP_GABA is impaired 2 hours after nicotine-injection. F, At 2 hours after exposure, averaged experiments show SNAP potentiation of IPSCs in slices from nicotine-treated animals (n = 7) is reduced compared to those from saline-treated animals (n = 7). There were significant effects of drug treatment (F_1,39 = 102.0, p < 0.001), time (F_1,39 = 5.1, p < 0.001) and an interaction between these two factors (F_1,39 = 1.99, p < 0.001). Scale bars: 10 ms, 50 pA.