Chronic Intermittent Ethanol Exposure Increases Ethanol Consumption Following Traumatic Stress Exposure in Mice

Area of Science:

• Neuroscience
• Behavioral Science
• Pharmacology

Background:

• Post-traumatic stress disorder (PTSD) and alcohol use disorder (AUD) frequently co-occur.
• Comorbid PTSD-AUD leads to heightened alcohol cravings and relapse rates.
• Animal models are needed to mechanistically explore PTSD-AUD behavioral effects.

Purpose of the Study:

• To investigate the effects of comorbid traumatic stress and alcohol exposure on ethanol intake, impulsivity, and anhedonia in mice.
• To establish and validate a mouse model for PTSD-AUD comorbidity.

Main Methods:

• Mice were exposed to mouse single-prolonged stress (mSPS) or control conditions.
• Chronic intermittent ethanol (CIE) vapor exposure was used to induce alcohol dependence.
• Ethanol intake, novelty suppressed feeding (NSF), and hedonic-like behavior were assessed.

Main Results:

• mSPS alone did not alter baseline ethanol consumption.
• Mice exposed to both mSPS and CIE showed increased ethanol consumption post-withdrawal.
• mSPS exposure increased impulsivity (shorter latency to feed), while CIE increased anhedonia (reduced palatable food intake).

Conclusions:

• The mSPS-CIE mouse model effectively mimics key behavioral aspects of PTSD-AUD comorbidity.
• Combined traumatic stress and alcohol exposure exacerbate withdrawal vulnerability.
• Specific behavioral deficits, impulsivity and anhedonia, are differentially affected by traumatic stress and chronic alcohol exposure.