Adolescent and adult nicotine exposure differentially impacts oral nicotine and oral saccharin self-administration in mice.

Adolescent and adult nicotine exposure differentially impacts oral nicotine and oral saccharin self-administration in mice.
Behav Brain Res. 2018 Jul 24;:
Authors: Cole RD, Wolsh C, Zimmerman M, Harrington E, Gould TJ, Parikh V
Abstract
Smokers that begin during adolescence are more likely to develop nicotine dependence than those who begin as adults. However, the factors that contribute to this remain largely unknown. Here we utilized a novel operant oral nicotine self-administration procedure in mice to assess the consequences of adolescent nicotine exposure on nicotine and saccharin (non-drug) reinforcement in adults. Animals were given non-contingent exposure to either saline or nicotine using the osmotic minipumps during both adolescence and adulthood for 2 weeks. Reinforcing efficacy for oral nicotine and saccharin was assessed using the progressive ratio schedule 2-weeks following the washout period in adults. Non-contingent nicotine exposure in adolescence drastically increased operant responding for oral nicotine but reduced responding for oral saccharin in the group re-exposed to nicotine in adulthood. Interestingly, adolescent nicotine-exposed mice that received saline exposure as adults exhibited higher preference for oral saccharin. However, breakpoints for oral nicotine in these mice remained comparable to control animals. Surprisingly, both adolescent and adult nicotine exposure increased inactive lever responding duri...

Source: Behavioural Brain Research - July 24, 2018 Category: Neurology Authors: Cole RD, Wolsh C, Zimmerman M, Harrington E, Gould TJ, Parikh V Tags: Behav Brain Res Source Type: research