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Updated: Jun 3, 2026
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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-induced impulsive action: sensitization and attenuation by mecamylamine
Ari P Kirshenbaum1, Eric R Jackson, Seth J Brown
1Saint Michael's College, Krikstone Lab for the Behavioral Sciences, Colchester, Vermont 05443, USA. akirshenbaum@smcvt.edu
Behavioural Pharmacology
|March 31, 2011
Summary
Nicotine impairs rats' ability to withhold responses, especially with repeated exposure. This effect, linked to nicotinic-acetylcholine receptor activation, suggests nicotine can increase impulsive behavior.
Area of Science:
- Neuroscience
- Behavioral Pharmacology
- Psychopharmacology
Background:
- Nicotine is a widely used psychoactive substance with complex effects on behavior.
- Understanding nicotine's impact on inhibitory control is crucial for addiction research.
- Response withholding is a key component of executive function and impulse control.
Purpose of the Study:
- To investigate the disinhibiting effects of nicotine on response withholding in rats.
- To examine the role of repeated nicotine administration and sensitization on inhibitory control.
- To determine if mecamylamine hydrochloride can attenuate nicotine-induced impulsivity.
Main Methods:
- Utilized a variable-interval differential-reinforcement-of-low-rate (VI-DRL) schedule and a stop-signal task in rats (n=18 each).
- Administered 0.3 mg/kg nicotine or saline, assessing performance after initial and repeated dosing.
- Tested the attenuating effects of mecamylamine hydrochloride (0.1-1.0 mg/kg) on nicotine's effects.
Main Results:
- Repeated nicotine administration, unlike initial doses, significantly decreased performance on both response withholding tasks.
- Sensitization to nicotine's effects on performance was observed with repeated dosing.
- Mecamylamine hydrochloride dose-dependently attenuated nicotine's disinhibiting effects, indicating a role for nicotinic receptors.
Conclusions:
- Nicotine, particularly with repeated exposure, impairs response withholding and promotes impulsive actions in rats.
- The observed behavioral effects are systematically related to the activation of nicotinic-acetylcholine receptors.
- These findings contribute to understanding nicotine's neurobiological mechanisms underlying behavioral disinhibition.
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