The Open Behavioral Science Journal

2010, 4 : 19-25
Published online 2010 September 9. DOI: 10.2174/1874230001004010019
Publisher ID: TOBSJ-4-19

Alterations of Emotional and Cognitive Behaviors in Matrix Metalloproteinase- 2 and -9-Deficient Mice

Hiroyuki Mizoguchi , Daisuke Ibi , Kazuhiro Takuma , Yuko Kitahara , Erika Toth , Jun Sato , Shigeyoshi Itohara , Toshitaka Nabeshima and Kiyofumi Yamada
Laboratory of Neuropsychopharmacology, Division of Life Sciences, Graduate School of Natural Science and Technology, Kanazawa University, Kanazawa, 920-1192, Japan.

ABSTRACT

Matrix metalloproteinases (MMPs) function to remodel the pericellular environment, and thereby play a crucial role in the remodeling of neural circuits. In the present study, we investigated the role of MMP-2 and MMP-9 in emotional and cognitive function using mice with targeted deletions of the MMP-2 and MMP-9 genes. Emotional behaviors of MMP-9-(-/-) mice but not MMP-2-(-/-) mice were altered, which was manifested in performances in the open-field and elevated plus-arm maze tests. MMP-9-(-/-) mice showed impairments in long-term object recognition memory and conditioned fear memory. MMP-2-(-/-) mice had no deficits in learning and memory. These findings suggest that endogenous MMP-9 play a role in emotional and cognitive behaviors, which may possibly be related to activitydependent synaptic plasticity and brain development.