Dose-dependent metabolite changes after ethanol intoxication in rat prefrontal cortex using in vivo magnetic resonance spectroscopy
Résumé
Ethanol disrupts the balance between the excitatory (glutamatergic) and inhibitory (GABAergic) neurotransmission systems. We aimed to assess how acute ethanol intoxication in rats affects the levels of GABA, glutamate and other cerebral metabolites after injection of two different doses of ethanol. One in vivo magnetic resonance spectrum of the prefrontal cortex region was acquired before and six spectra were acquired after intraperitoneal injections of saline or ethanol (1 g/kg or 2 g/kg). Brain kinetics after exposure to ethanol were compared to blood ethanol kinetics. GABA levels significantly decreased after injection of 1 g/kg but not 2 g/kg doses of ethanol. Choline levels, which serve as a marker of alterations in membrane composition, significantly decreased after injection of 2 g/kg but not 1 g/kg doses of ethanol. Acute ethanol intoxication appears to result in specific dose-dependent changes in the GABA level and choline level.