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Spectral Confocal Imaging of Fluorescently tagged Nicotinic Receptors in Knock-in Mice with Chronic Nicotine Administration
Published on: February 10, 2012
Nicotine preference and affective behavior of Cd81 knockout mice
R Logan Murphy1,2, Laura L Locklear1,3, M Haris Niaz1
1School of Systems Biology, and the Interdisciplinary Program in Neurosciences, George Mason University, Mail Stop 1J1, Institute of Advanced Biomedical Research Building, 10920 George Mason Circle, Manassas, VA, 20110, USA.
Mice lacking the Cd81 gene show increased nicotine preference and withdrawal symptoms. These findings suggest a potential link between Cd81 and stress-related behaviors, warranting further investigation into its role in addiction and trauma responses.
Area of Science:
- Neuroscience
- Behavioral Pharmacology
- Genetics
Background:
- Previous research indicated Cd81 knockout mice have altered dopamine levels and cocaine preference.
- The impact of Cd81 on behaviors related to other drugs of abuse remained unexplored.
Purpose of the Study:
- To investigate the effects of Cd81 gene deletion on nicotine consumption and withdrawal.
- To assess the influence of Cd81 on affective behaviors and tyrosine hydroxylase gene expression.
Main Methods:
- Utilized a two-bottle choice test for nicotine preference in Cd81 knockout mice.
- Evaluated somatic signs of nicotine withdrawal and performed four tests for affective behavior.
- Assayed tyrosine hydroxylase gene expression levels.
Main Results:
- Cd81 loss-of-function significantly elevated voluntary nicotine consumption and somatic signs of withdrawal.
- Increased struggling in the forced swim test and light chamber preference in the light/dark box were observed.
- No significant effects on anxiety- or depression-like behaviors were found in the elevated plus maze or tail suspension test. Tyrosine hydroxylase mRNA levels remained unchanged.
Conclusions:
- Cd81 knockout mice exhibit a pronounced increase in nicotine preference and heightened responses to stress.
- These findings, coupled with prior observations of altered dopamine and reports of aggression, suggest parallels with post-traumatic stress disorder.

