A study examining intravenous ethanol-conditioned place preference in C57BL/6J mice

Area of Science:

• Neuroscience
• Pharmacology
• Behavioral Science

Background:

• Ethanol (alcohol) is a widely consumed psychoactive substance with known reinforcing properties.
• Understanding the neurobiological mechanisms underlying ethanol's rewarding effects is crucial for developing effective addiction treatments.
• The C57BL/6J mouse strain is a common model for studying alcohol's effects due to its genetic background.

Purpose of the Study:

• To investigate the reinforcing effects of intravenous (I.V.) ethanol in C57BL/6J mice using a conditioned-place-preference (CPP) paradigm.
• To compare the subjective effects of I.V. ethanol with intraperitoneally administered ethanol.

Main Methods:

• Adult C57BL/6J mice underwent jugular catheterization for I.V. infusions.
• A conditioned-place-preference (CPP) paradigm was used, pairing I.V. ethanol with a non-preferred compartment and saline with a preferred compartment.
• A separate drug discrimination task assessed the subjective effects of I.V. ethanol versus intraperitoneal ethanol.

Main Results:

• Significant conditioned place preference (CPP) was observed after only two pairings with I.V. ethanol (0.82 g/kg/day).
• Control mice receiving saline did not show changes in compartment preference.
• Substitution testing in the drug discrimination paradigm indicated that the subjective effects of I.V. and intraperitoneal ethanol were similar.

Conclusions:

• Intravenous ethanol administration is rewarding in C57BL/6J mice, as demonstrated by the CPP paradigm.
• The subjective effects of ethanol are comparable regardless of whether it is administered intravenously or intraperitoneally.
• These findings support the use of I.V. ethanol administration in preclinical models to study alcohol's reinforcing properties.