The Effect of Ketamine on Motor Coordination and Thermal Nociception in Ethanol-Withdrawn Mice

This experiment aimed to establish a model for long and/or short-term ethanolwithdrawal induced motor deficits and thermal sensitivity in mice. Additionally, the effects of ketamine on these phenomena were evaluated. Human studies of alcoholics have documented, along with behavioral depression, deficiencies in gait and balance, as well as an increase in pain sensitivity, immediately following abstinence, and in some cases, lasting many years. Ketamine, an NMDA antagonist, has been shown alleviate behavioral depression in both animal and human models, but its physiological mechanisms are still being evaluated. Ethanol dependence was induced using chronic intermittent alcohol vapor exposure. Low-dose ketamine was injected immediately following the 8-day ethanol vapor protocol. Animals were then tested for motor coordination via an accelerating rotarod (ARR), and for thermal nociception via the radiant heat tail-flick test. Tests were run at 6 hours, 24 hours, then each day for two weeks post-withdrawal. Data show a significant, late-emerging effect of ethanol on ARR scores, establishing a novel model for long-term ethanol withdrawal-induced motor coordination deficiencies in mice. Additionally, no effects of ketamine were observed. Finally, No effects of either ethanol or ketamine were seen in the tail-flick assay.