Skip to main content
Figure 6 | BMC Neuroscience

Figure 6

From: Chronic nicotine pretreatment is sufficient to upregulate α4* nicotinic receptors and increase oral nicotine self-administration in mice

Figure 6

Chronic nicotine pump mice self-administer a greater amount of nicotine and display a surge in nicotine consumption following abstinence. A) Following 10 days of chronic drug administration via osmotic pumps (2 mg/kg/hr nicotine or saline), mice are subjected to five 7 day cycles of choice (4 days, two bottle: vehicle (0.2% saccharine) or vehicle + 200 μg/ml nicotine) followed by abstinence (3 days, single bottle roH2O). During choice period, nicotine primed mice consumed a greater dose of nicotine than saline pump mice (p 0.0496, pump factor, two-way mixed ANOVA). Mice implanted with a nicotine pump (n = 14) self-administered more nicotine during W1 (*p = 0.003, pump factor, two-way ANOVA), W3 (**p = 0.02, pump factor, two-way ANOVA) and W5 (***p = 0.006, pump factor, two-way ANOVA). B) Mean nicotine dose averaged each week of two bottle-choice self-administration showed that on a weekly basis nicotine pump mice self-administered a significantly higher level of nicotine than saline pump mice (p = 0.0496, pump factor effect, two-way mixed ANOVA; W1, p = 0.002; W3, p = 0.04; W5, p = 0.01, Bonferroni post-hoc analysis). C) Nicotine binge-drinking following abstinence from nicotine self-administration occurred only in the nicotine pump mice. In nicotine pump mice there was elevated nicotine consumption the day following abstinence followed by a steady decline thereafter in the next three days of choice (Solid line: R2 = 0.77, *p = 0.01). Saline pump mice consumed a lower dose throughout each day of the choice period (dashed line: R2 = 0.70, p = 0.56). Nicotine pump mice also showed a significant transient elevation in their nicotine consumption on the first day (p = 0.03, Wilcoxon rank sum test) following abstinence as compared to saline pump mice.

Back to article page