Figure 1.

Mecamylamine-induced somatic signs of withdrawal in wild-type, α2−/− and α5−/− mice. A, Mice receiving nicotine via osmotic minipumps. Total nicotine withdrawal signs in control mice (+/+) treated with saline (n = 10, black bars) or nicotine (n = 16, white bars), α2−/− mice treated with saline (n = 8, dark gray bars) or nicotine (n = 12, white bars), and α5−/− mice treated with saline (n = 9, light gray bars) or nicotine (n = 13, white bars) during the 20 min immediately after mecamylamine injection. B, Mice treated with nicotine in the drinking water. Total nicotine withdrawal signs over 10 min in control mice (+/+) treated with saline (n = 17, black bars) or nicotine (n = 8, white bars), and α5−/− mice treated with saline (n = 8, dark gray bars) or nicotine (n = 13, white bars). *p < 0.05 versus +/+ saline (ANOVA and LSD post hoc comparisons). Error bars represent SEM.