Figure 1.

Seizure incidence, blood ethanol levels and Ba²⁺ currents. A. At 24 h during ethanol withdrawal, all tested animals (n=10) exhibited wild running seizures (WRS) that evolved into bouncing generalized tonic-clonic seizures (clonus). No seizure susceptibility was observed 3 h (n=8) or 48 h (n=8) during ethanol withdrawal or in the control group (n=8) or 3 h after ethanol intoxication. The seizure incidence was significantly (P<0.001; χ²) elevated 24 h compared with 3 h and 48 h during ethanol withdrawal, 3 h after ethanol intoxication and the control group. B. Blood ethanol concentrations (BECs) were also significantly elevated 3 h during ethanol intoxication (n=6) compared with the control group (n=6, P<0.05, Bonferroni’s test) and the group tested 3 h during ethanol withdrawal (n=6, P<0.05, Bonferroni’s test). During ethanol withdrawal, BECs were significantly elevated 3 h (n=6, P<0.05, Bonferroni’s test) but negligible 24 h (n=6) and 48 h (n=6) during ethanol withdrawal compared with the control group (n=6). BECs measured 3 h during ethanol withdrawal were significantly (n=6, P<0.05, Bonferroni’s test) elevated compared with 24 h or 48 h during ethanol withdrawal. C. The mean peak Ba²⁺ current density in IC neurons was significantly higher 3 h (n=14, P<0.05, Bonferroni’s test), 24 h (n=18, t=5.9, P<0.05, Bonferroni’s test) and 4h (n=16, t=3, P<0.05, Bonferroni’s test) during ethanol withdrawal than in the control group (n=18). The current density was also significantly higher 24 h (n=18, P<0.05, Bonferroni’s test) than 48 h (n=16) following ethanol withdrawal. The mean peak Ba²⁺ current density 3 h (n=14, P<0.05, Bonferroni’s test) following ethanol withdrawal was significantly enhanced in IC neurons compared with 3 h (n=10) after ethanol intoxication. The current density was not altered in IC neurons after ethanol intoxication compared with the control group. Ba²⁺ currents were activated as shown in the inset. Each bar graph represents the mean ± S.E.M or percentage (%). *P<0.05, ***P<0.001.