Multiphasic Consequences of the Acute Administration of Ethanol on Cerebral Glucose Metabolism in the Rat

Wake Forest University School of Medicine, Department of Physiology and Pharmacology, Medical Center Boulevard, Winston-Salem, NC 27157, USA
Pharmacology Biochemistry and Behavior (Impact Factor: 2.61). 11/1998; DOI:10.1016/S0091-3057(98)00089-6

ABSTRACT The present study investigated the role of the postinjection interval in determining the functional consequences of acute ethanol administration in the CNS. Local cerebral metabolic rates for glucose (LCMRglc) were determined by the 2[14C]deoxyglucose method in 48 brain structures of ethanol-naive Sprague–Dawley rats. Tracer was injected 1 or 45 min after a 0.8 g/kg intragastric dose of ethanol or water. At the early time point, LCMRglc was increased in a highly restricted portion of the basal ganglia that included the dorsal striatum, globus pallidus, and core of the nucleus accumbens, compared to water controls. No significant decreases were found at this early time point. At the later time point, by contrast, LCMRglc was decreased in a different set of brain structures. These sites were limbic in nature and included the infralimbic and anterior cingulate cortices, dentate gyrus, lateral septum, and the bed nucleus of the stria terminalis. These data indicate that there are multiple phases that can be detected during the time course of an acute dose of ethanol. They further demonstrate the involvement of different neural systems at the two time points. Increased activity in basal ganglia is consistent with stimulated motor activity, whereas diminished activity in limbic sites may correspond to changes in mood and motivation.

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