The effects of ethanol and ethanol metabolites on locomotor activity: Role of the substantia nigra pars reticulata

Date of Completion

January 2004


Psychology, Psychobiology|Health Sciences, Pharmacology




Ethanol has long been categorized as a sedative-hypnotic, however more and more evidence is mounting that suggests that ethanol also has stimulant properties on behavior. The current study examined the ability of ethanol and ethanol metabolites to induce locomotor activity after direct infusion into the substantia nigra pars reticulata. It was found that ethanol and acetaldehyde induced locomotor activity following intranigral infusion, but not in a dorsal control site or in posterior brainstem areas. In addition the ethanol-induced activity could be attenuated by inhibiting central ethanol metabolism with the catalase inhibitor sodium azide. Acetate also produced an increase in locomotor behavior, however it was found that this increase was due to the pH of the acetate solution used. Once pH was adjusted to the level of vehicle, acetate no longer produced an increase in locomotor activity. Lastly, the locomotor-activating dose of ethanol was used to assess the effect of ventral tegmental area (VTA) infusions on locomotor behavior. It was found that the VTA was also an active site for ethanol-induction of locomotor behavior. ^