Abstract
Drug abuse runs in families suggesting the involvement of genetic risk factors. Differences in addiction-related neurobiological systems, including learning and memory and circadian rhythms, may exist prior to developing addiction. We characterized the cognitive phenotypes and the free-running circadian period of mouse lines selectively bred for high methamphetamine (MA) drinking (MA high drinking or MAHDR) and low MA drinking (MA low drinking or MALDR). MA-naïve MALDR mice showed spatial memory retention while MAHDR mice did not. MA-naïve MAHDR mice had elevated hippocampal levels of the AMPA receptor subunits GluA2 (old terminology: GluR2), but not GluA1 (old terminology: GluR1). There were no line differences in the free running period (. τ) when only water was available. During a 25. mg/L MA solution access period (vs water), there was an increase in τ in MALDR but not MAHDR mice, although MAHDR mice consumed significantly more MA. During a 50. mg/L MA solution access period (vs water), both lines showed an increased τ. There was a positive correlation between MA consumption and τ from baseline in MALDR, but not MAHDR, mice. Thus, a heritable proclivity for elevated MA self-administration may be associated with impairments in hippocampus-dependent memory and reduced sensitivity to effects of MA on lengthening of the circadian period.
Original language | English (US) |
---|---|
Pages (from-to) | 197-204 |
Number of pages | 8 |
Journal | Behavioural Brain Research |
Volume | 256 |
DOIs | |
State | Published - Nov 1 2013 |
Keywords
- Circadian
- GluA1/2
- Glutamate receptors
- Methamphetamine
- Spatial memory
- Water maze
ASJC Scopus subject areas
- Behavioral Neuroscience