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Published on: June 22, 2015
Behavioral screening of two mouse lines selected for different brain weight
N V Markina1, R M Salimov, I I Poletaeva
1Department of Biology, Lomonossov Moscow State University, Russia.
Summary
Small brain (SB) mice exhibit heightened anxiety, pain sensitivity, and altered locomotion compared to large brain (LB) mice. Ethanol affects their maze exploration differently, impacting stereotypy similarly.
Area of Science:
- Neuroscience
- Behavioral Genetics
Background:
- Brain-to-body weight ratio is a key factor in behavioral research.
- Understanding genetic influences on brain size and behavior is crucial.
Purpose of the Study:
- To compare behavioral phenotypes of mice selectively bred for large (LB) and small (SB) brain weights.
- To investigate anxiety-like behaviors, pain sensitivity, and responses to ethanol in these distinct mouse lines.
Main Methods:
- Utilized various behavioral tests including open field, cross-maze, slip funnel, and tail suspension tests.
- Administered acute ethanol (3 g/kg) to assess its effects on maze exploration and stereotypy.
- Compared behavioral responses between LB and SB mice lines.
Main Results:
- SB mice displayed increased pain sensitivity and startle responses compared to LB mice.
- Higher immobility in SB mice during inescapable tests indicated elevated fear/anxiety.
- SB mice showed increased locomotion and stereotyped arm alternation in maze tests.
- Ethanol increased maze exploration time in SB mice but decreased it in LB mice, while increasing stereotypy in both.
Conclusions:
- Selective breeding for brain size influences behavioral traits related to anxiety, pain, and locomotion.
- SB mice exhibit a distinct behavioral profile suggestive of higher anxiety and altered stress responses.
- Ethanol's effects on behavior are differential between LB and SB mice, particularly concerning maze exploration efficacy.
