•P21, P35 and P63 female Swiss mice (P=post-natal day)
•Ethanol doses: 0, 1.5, 2, 2.5, 3.5, 4 g/kg
•7 daily administrations (i.p.)
•Sessions: acute and sensitization
(locomotor activity during 30 minutes)
Caroline Quoilin, Vincent Didone, and Etienne Quertemont Quantitative Psychology, University of Liège, Belgium
Stimulant effects of ethanol in adolescent Swiss mice: development
of sensitization and consequences in adulthood
Introduction
Ontogeny of sensitization
Consequences in adulthood
The adolescent period is characterized by behavioral and neurobiological changes. These changes could predispose adolescents to experiment with alcohol, and to be particularly vulnerable to the long-term consequences of its use, such as increased risks of later dependence when drinking is initiated early.
Hypothesis: adolescent vulnerability to alcohol is partially explained by an altered sensitivity to chronic ethanol-induced neuroadaptations.
Aims: - investigation of potential differences in the development and expression of sensitization to the stimulant effects of various ethanol doses in female Swiss mice
- characterization of changes in sensitivity to the stimulant effects of ethanol in adult female Swiss mice with a history of chronic alcohol intoxication during adolescence.
•Chronic exposure to ethanol during adolescence:
14 daily injections (i.p.) from P28 to P41 of 0, 2.5 or 4 g/kg ethanol
•Reexposure to ethanol (adulthood):
- Acute session at P63: 2.5 g/kg ethanol - 6 daily injections of 2.5 g/kg ethanol (locomotor activity during 30 minutes)
Conclusions
Contact information:caroline.quoilin@ulg.ac.be Ethanol dose (g/kg) 0 1.5 2 2.5 3.5 4 L o co m o to r a ct iv it y ( co u n ts /5 m in ) 0 50 100 150 200 250 300 P21 P35 P63 * ** ** ** ** ** *** *** ****** *** Acute session Ethanol dose (g/kg) 0 1.5 2 2.5 3.5 4 P er ce n ta g e in cr ea se i n l o co m o to r a ct iv it y 0 100 200 300 400 500 600 P27 P41 P69 ** ** ** ** ** *** *** Sensitization: percentage increase
- Test session: at P70: 2.5 g/kg ethanol
Younger mice are more sensitive to the stimulant effects of acute ethanol, but require higher ethanol doses to develop sensitization. However, when sensitization develops, younger mice reach sensitized stimulant effects that are much higher than in adults. Adolescent mice develop very strong ethanol sensitization at doses that mimic binge drinking in humans.
Moreover, repeated ethanol exposure during adolescence induces long-lasting effects, with higher ethanol stimulant effects in adulthood.
Time Intervals 1 2 3 4 5 6 L o co m o to r a ct iv it y ( co u n ts ) 0 100 200 300 400 Saline EtOH 2.5 EtOH 4
Adolescence ethanol exposure (g/kg)
0 2.5 4 L o co m o to r a ct iv it y ( c o u n ts /5 m in ) 0 100 200 300 400 * Test session (P70) Time Intervals 1 2 3 4 5 6 L o co m o to r a ct iv it y ( co u n ts ) 0 50 100 150 200 250 300 Saline EtOH 2.5 EtOH 4
Adolescence ethanol exposure (g/kg)
0 2.5 4 L o co m o to r a ct iv it y ( co u n ts /5 m in ) 0 50 100 150 200 250 300 *** Acute session (P63)
