Abstract
Metabotropic glutamate receptors modulate glutamatergic and GABAergic neurotransmission. Our previous pharmacological data indicate that metabotropic receptor 4 (mGlu4) and metabotropic receptor 8 (mGlu8) might have related and overlapping functions. We explored this by analyzing the behavioral phenotypes of mice deficient in either (mGlu4-/- or mGlu8-/-) or both receptors (mGlu4/8-/-). Our analysis focused on measures of anxiety in the open field and elevated zero maze, sensorimotor function on the rotarod and fear conditioning, as mGlu4 and/or mGlu8 were shown to affect performance in these tests. mGlu8-/- mice weighed more than mGlu4/8-/- mice. In the open field, mGlu4-/- mice showed lower levels of anxiety than mGlu8-/- and mGlu4/8-/- mice. In the elevated zero maze, mGlu4-/- mice showed lower levels of anxiety than wild-type, mGlu8-/- and mGlu4/8-/- mice. In the open field, but not elevated zero maze, mGlu4-/- mice showed lower activity levels than wild-type, mGlu8-/- and mGlu4/8-/- mice. mGlu4/8 -/- female mice showed less contextual freezing than wild-type and mGlu4-/- female mice and there was a trend toward less freezing in male mGlu4/8-/- than wild-type male mice. There were no genotype differences in cued fear conditioning. There were significant negative correlations between body weight and fall latency on the rotarod in wild-type, mGlu8-/- and mGlu4/8-/-, but not mGlu4-/-, mice. These data suggest related functions of mGlu4 and mGlu8 in behavioral performance.
Original language | English (US) |
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Pages (from-to) | 11-16 |
Number of pages | 6 |
Journal | Pharmacology Biochemistry and Behavior |
Volume | 111 |
DOIs | |
State | Published - 2013 |
Keywords
- Body weight
- Fear conditioning
- Open field
- Zero maze
- mGlu4
- mGlu8
ASJC Scopus subject areas
- Biochemistry
- Toxicology
- Pharmacology
- Clinical Biochemistry
- Biological Psychiatry
- Behavioral Neuroscience