Biphasic effect of ethanol on noradrenaline release in the frontal cortex of awake rats.
Ethanol elicited a biphasic effects on the extracellular noradrenaline (NA) concentrations in the rat frontal cortex, as assessed by microdialysis in awake animals. A low dose of ethanol (0.2 g/kg i.p.) raised NA output to about 160% of baseline levels. In contrast, a dose of 2 g/kg inhibited NA output to about 70% of pre-drug levels. These results suggest that the decrease in cortical NA output may reflect the sedative-hypnotic properties of ethanol at high doses, whereas the stimulation of extraneuronal NA may represent a biochemical correlate of the arousal and increased alertness elicited by low doses of ethanol.
Rossetti
Z L
ZL
B. B. Brodie Department of Neuroscience, Cagliari, Italy.
Longu
G
G
Mercuro
G
G
Hmaidan
Y
Y
Gessa
G L
GL
D000818:Animals; D001143:Arousal / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D000431:Ethanol / Q000494:pharmacology*; D008297:Male; D009638:Norepinephrine / Q000378:metabolism*; D017397:Prefrontal Cortex / Q000187:drug effects* / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley
D000431:Ethanol; D009638:Norepinephrine