Ethanol oral self-administration and rewarding brain stimulation.
The effects of orally self-administered ethanol (ETOH) on responding for rewarding brain stimulation were studied. Bipolar electrodes were implanted in either the lateral hypothalamic region of the medial forebrain bundle (MFB-LH) or the ventral tegmental area (VTA) of 6 male F-344 rats. After surgery subjects were trained in a continuous reinforcement procedure (CRF) for constant current rewarding brain stimulation. On alternate days subjects were allowed to drink an ethanol and sucrose solution (12% and 5%, respectively) for 30 min and subsequently tested on the brain stimulation procedure. All subjects showed facilitation of responding (increase in rate) after ingesting low to moderate doses of ETOH (0.4-1.7 g/kg). Depression of responding (decrease in rate) or return to baseline levels (control solution rate) was observed only in those subjects which ingested 2 g/kg or greater during the drinking period. These results indicate that low to moderate doses of self-administered ethanol will increase responding for rewarding brain stimulation. Further, the results suggest that this facilitation of responding is, at least in part, a function of the method of administration and/or the contingent nature of the ethanol delivery (self-administration).
Bain
G T
GT
Laboratory of Behavioral Pharmacology, Boston University School of Medicine, MA 02118.
Kornetsky
C
C
D000284:Administration, Oral; D000704:Analysis of Variance; D000818:Animals; D001921:Brain / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D000431:Ethanol / Q000494:pharmacology*; D008297:Male; D051381:Rats; D011916:Rats, Inbred F344; D012201:Reward; D012646:Self Administration
D000431:Ethanol