Published in:
Open Access
01-12-2012 | Research
Vldlr overexpression causes hyperactivity in rats
Authors:
Keiko Iwata, Nobuo Izumo, Hideo Matsuzaki, Takayuki Manabe, Yukiko Ishibashi, Yukio Ichitani, Kazuo Yamada, Ismail Thanseem, Ayyappan Anitha, Mahesh Mundalil Vasu, Chie Shimmura, Tomoyasu Wakuda, Yosuke Kameno, Taro Takahashi, Yasuhide Iwata, Katsuaki Suzuki, Kazuhiko Nakamura, Norio Mori
Published in:
Molecular Autism
|
Issue 1/2012
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Abstract
Background
Reelin regulates neuronal positioning in cortical brain structures and neuronal migration via binding to the lipoprotein receptors Vldlr and Lrp8. Reeler mutant mice display severe brain morphological defects and behavioral abnormalities. Several reports have implicated reelin signaling in the etiology of neurodevelopmental and psychiatric disorders, including autism, schizophrenia, bipolar disorder, and depression. Moreover, it has been reported that VLDLR mRNA levels are increased in the post-mortem brain of autistic patients.
Methods
We generated transgenic (Tg) rats overexpressing Vldlr, and examined their histological and behavioral features.
Results
Spontaneous locomotor activity was significantly increased in Tg rats, without detectable changes in brain histology. Additionally, Tg rats tended to show performance deficits in the radial maze task, suggesting that their spatial working memory was slightly impaired. Thus, Vldlr levels may be involved in determining locomotor activity and memory function.
Conclusions
Unlike reeler mice, patients with neurodevelopmental or psychiatric disorders do not show striking neuroanatomical aberrations. Therefore, it is notable, from a clinical point of view, that we observed behavioral phenotypes in Vldlr-Tg rats in the absence of neuroanatomical abnormalities.