Increased Risky Choice and Reduced ChRNB2 Expression in adult Male Rats Exposed to Nicotine Vapor.

Introduction:
This text discusses a study on the effects of nicotine vapor exposure on risky decision making and the mechanisms that drive choice. The study uses a probability discounting task to assess risky choice and investigates the long-term effects of nicotine on cholinergic gene expression. The study also considers the impact of nicotine withdrawal on gene expression.

Key Points:

* The study used a four-chamber passive vapor inhalation system to expose rats to nicotine vapor.
* Nicotine vapor exposure caused modest and transient effects on decision making.
* The study found reduced nicotinic receptor subunit gene expression in subjects with a history of vapor exposure.
* The reduction in nicotinic receptor subunit gene expression may be a long-term mechanism driving relapse in e-cigarette users.
* The study also found reduced DRD1 and DRD2 expression in the nucleus accumbens core and medial prefrontal cortex.
* The study used a subset of 24 rats from the 32 rats used for behavioral testing for analysis of gene expression.
* The study used RT-PCR to assess mRNa levels and inferred target gene expression based on analyses of associated mRNa.

Main Message:
The study provides important data on the negative behavioral and cognitive effects of nicotine vapor exposure, which is crucial given the recent increases in recreational e-cigarette use. The analysis also serves to extend the current understanding of nicotine's possible effects on mechanisms underlying decision making. The observed reduction in nicotinic receptor subunit gene expression observed in subjects with a history of vapor exposure, versus those without, may be a distinct long-term mechanism driving relapse in e-cigarette users. Overall, the study highlights the need for additional work on how nicotine vapor exposure affects cholinergic mechanisms and how these changes impact decision making.

Giner P, Maynez-anchondo L, Liley aE, et al. Increased Risky Choice and Reduced ChRNB2 Expression in adult Male Rats Exposed to Nicotine Vapor. Int J Mol Sci. 2022;23:1231. doi:10.3390/ijms23031231