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Updated: Jun 5, 2026
10:28
Assessment of Cocaine-induced Behavioral Sensitization and Conditioned Place Preference in Mice
Published on: February 18, 2016
Methamphetamine-induced locomotor changes are dependent on age, dose and genotype
Renee L Good1, Richard A Radcliffe
1University of Colorado Anschutz Medical Campus, Department of Pharmaceutical Sciences, PO Box 6511, Aurora, CO 80045, United States. Renee.Good@ucdenver.edu
Pharmacology, Biochemistry, and Behavior
|December 18, 2010
Summary
Adolescent methamphetamine exposure impacts adult behavior differently based on mouse strain and dose. Age, genetics, and drug dosage significantly influence addiction-related locomotor responses.
Area of Science:
- Neuroscience
- Pharmacology
- Addiction Research
Background:
- Adolescence is a critical period for addiction development.
- Neurotoxic effects of drugs of abuse on behavior are understudied.
- Methamphetamine (METH) abuse leads to complex behavioral changes like sensitization and tolerance.
Purpose of the Study:
- Investigate how age, genotype, METH dose, and metabolism affect open-field activity (OFA).
- Understand the neurobiological underpinnings of drug abuse vulnerability.
- Examine METH's long-term effects on behavior.
Main Methods:
- Administered saline or high/low dose METH to adolescent and adult mice of three strains (B6, D2, 129).
- Assessed behavioral responses (locomotion) to a METH challenge 40 days later.
- Measured striatal METH and AMPH concentrations.
Main Results:
- Adolescent B6 mice showed METH sensitization in horizontal locomotion after high-dose pretreatment.
- Adult B6 mice exhibited tolerance in vertical activity after low-dose METH.
- Adult D2 mice displayed sensitization in vertical activity after low-dose METH.
- 129 mice metabolized METH faster, but METH pretreatment did not affect metabolism.
Conclusions:
- Age, mouse strain, and METH dose interact to influence locomotor behaviors.
- These factors are crucial for understanding addiction vulnerability.
- Results highlight the complexity of METH's neurobiological effects.
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