Background: The addition of sucrose to ethanol solutions results in a subst
antial increase in ethanol self-administration by rats that are deprived of
neither food nor water. however, if sucrose alters ethanol absorption or m
etabolism, resulting in blood ethanol concentrations (BECs) not different f
rom those resulting from lower intakes of ethanol/water solutions, then the
usefulness of sucrose/ethanol mixtures in increasing ethanol consumption i
s questionable. The present study was conducted to determine whether the ad
dition of sucrose to ethanol solutions altered BECs in an operant self-admi
nistration paradigm.
Methods: Tail blood (from male Long-Evans rats) was collected 30 min after
the intake of four different solutions, i.e., 5% sucrose/20% ethanol, 5% su
crose/10% ethanol,2% sucrose/10% ethanol, and 10% ethanol.
Results: Ethanol intakes (mean, 1.57 +/- 0.21 g/kg) and BECs (mean, 78.4 +/
- 9.3 mg/100 ml) were highest when 5% sucrose was added to the ethanol solu
tion. Moreover, the ratios between ethanol intakes and resulting BECs were
approximately the same for all solutions.
Conclusions: These findings indicate that, under the conditions of this pro
cedure, the BEC reached is dependent on the amount of ethanol consumed and
is not influenced by the addition of sucrose to the solution.