Sex and pain modality differentially modulate alcohol consumption in mice

Area of Science:

• Neuroscience
• Pharmacology
• Behavioral Science

Background:

• Chronic pain is linked to increased alcohol consumption and alcohol use disorders (AUD).
• Preclinical models are crucial for understanding the mechanisms connecting pain and alcohol use.
• Investigating these links can inform strategies for managing co-occurring pain and AUD.

Purpose of the Study:

• To investigate how different types of chronic pain influence alcohol intake and preference in mouse models.
• To determine if alcohol consumption affects pain sensitivity in the context of chronic pain.
• To explore the role of kappa opioid receptors in the pain-alcohol interaction.

Main Methods:

• Utilized mouse models to induce chronic pain using Complete Freund's Adjuvant (CFA) or paclitaxel.
• Measured ethanol intake and preference using the two-bottle choice paradigm.
• Administered a selective kappa antagonist (nor-BNI) to assess its effects on alcohol intake and pain sensitivity.

Main Results:

• CFA-induced pain increased alcohol intake and preference in male mice, an effect reversed by nor-BNI.
• Paclitaxel-induced pain decreased alcohol intake and preference in male mice.
• Ethanol consumption partially reduced CFA-induced mechanical hypersensitivity in male mice, but not in females.

Conclusions:

• The relationship between chronic pain and alcohol consumption is complex, varying significantly by sex and the specific pain model.
• Kappa opioid pathways play a role in mediating increased alcohol intake associated with certain types of chronic pain.
• Alcohol consumption may have differential effects on pain perception depending on the pain etiology and sex.