Loading...
Maladaptive defensive behaviours in monoamine oxidase A-deficient mice
Godar, Sean C. Bortolato, Marco Frau, Roberto Dousti, Mona Chen, Kevin Shih, Jean C.
Godar, Sean C.
Bortolato, Marco
Frau, Roberto
Dousti, Mona
Chen, Kevin
Shih, Jean C.
Citations
Altmetric:
Abstract
Rich evidence indicates that monoamine oxidase (MAO) A, the major enzyme catalysing the degradation of monoamine neurotransmitters, plays a key role in emotional regulation. Although MAOA deficiency is associated with reactive aggression in humans and mice, the involvement of this enzyme in defensive behaviour remains controversial and poorly understood. To address this issue, we tested MAOA knockout (KO) mice in a spectrum of paradigms and settings associated with variable degrees of threat. The presentation of novel inanimate objects induced a significant reduction in exploratory approaches and increase in defensive behaviours, such as tail-rattling, biting and digging. These neophobic responses were context-dependent and particularly marked in the home cage. In the elevated plus- and T-mazes, MAOA KO mice and wild-type (WT) littermates displayed equivalent locomotor activity and time in closed and open arms; however, MAOA KO mice featured significant reductions in risk assessment, as well as unconditioned avoidance and escape. No differences between genotypes were observed in the defensive withdrawal and emergence test. Conversely, MAOA KO mice exhibited a dramatic reduction of defensive and fear-related behaviours in the presence of predator-related cues, such as predator urine or an anaesthetized rat, in comparison with those observed in their WT littermates. The behavioural abnormalities in MAOA KO mice were not paralleled by overt alterations in sensory and microvibrissal functions. Collectively, these results suggest that MAOA deficiency leads to a general inability to appropriately assess contextual risk and attune defensive and emotional responses to environmental cues.
Description
This is the publisher's version, also available electronically from http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=8369466&fileId=S1461145710001483
Date
2011-10
Journal Title
Journal ISSN
Volume Title
Publisher
Cambridge University Press
Collections
Files
Research Projects
Organizational Units
Journal Issue
Keywords
Anxiety, Defensive behaviour, Exploration, Monoamine oxidase A, Predator urine
Citation
Sean C. Godar et al. (2011). Maladaptive defensive behaviours in monoamine oxidase A-deficient mice. The International Journal of Neuropsychopharmacology 14:1195-1207. http://dx.doi.org/10.1017/S1461145710001483