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Updated: Jun 16, 2026
09:12
Three Laboratory Procedures for Assessing Different Manifestations of Impulsivity in Rats
Published on: March 17, 2019
Yohimbine increases impulsivity through activation of cAMP response element binding in the orbitofrontal cortex
HaoSheng Sun1, Thomas A Green, David E H Theobald
1Department of Psychology, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada.
Biological Psychiatry
|February 19, 2010
Summary
Stress increases impulsivity, and yohimbine exacerbates this effect by altering cyclic adenosine monophosphate response element binding (CREB) protein activity in the orbitofrontal cortex. This suggests a novel molecular mechanism linking stress and impulsivity.
Area of Science:
- Neuroscience
- Psychiatry
- Molecular Biology
Background:
- Stress significantly impacts psychiatric conditions by increasing impulsivity.
- Norepinephrine and alpha(2) antagonists like yohimbine are key in studying stress responses.
- Yohimbine's effects on impulsivity and anxiety vary across populations, worsening outcomes in bipolar and substance-dependent individuals.
Purpose of the Study:
- To investigate the neurobiological mechanisms underlying yohimbine-induced impulsivity.
- To explore the role of cyclic adenosine monophosphate response element binding (CREB) protein in the orbitofrontal cortex's regulation of impulsivity.
Main Methods:
- Rats were tested for impulsivity using the five-choice serial reaction time test after yohimbine administration.
- CREB protein activity in brain regions regulating impulsivity was assessed.
- Viral-mediated gene transfer was used to manipulate CREB and mCREB expression in the orbitofrontal cortex.
Main Results:
- Yohimbine increased impulsive behavior in rats.
- Yohimbine selectively elevated CREB phosphorylation in the orbitofrontal cortex.
- Modulating CREB activity in the orbitofrontal cortex directly affected yohimbine's impact on impulsivity.
Conclusions:
- A novel molecular pathway involving CREB in the orbitofrontal cortex contributes to stress-sensitive impulsivity.
- These findings offer insights into the neurobiological links between stress, impulsivity, and psychiatric disorders.
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