Behavioral assessment of the visual ability of β2-microglobulin knockout mice

DOI Web Site
  • Shimbo Akihiro
    Graduate School of Human Relations, Department of Psychology, Keio University
  • Kakitani Tukasa
    Graduate School of Human Relations, Department of Psychology, Keio University
  • Ito Isao
    Department of Biology, Faculty of Science, Kyushu University
  • Watanabe Shigeru
    Advanced Research Centers, Keio University

Bibliographic Information

Other Title
  • β2-microglobulinノックアウトマウスにおける視覚能力の行動評価

Search this article

Abstract

<p>The left-right asymmetry has been demonstrated in the mouse hippocampal CA3-CA1 connection not only at a gross anatomical level but also at the molecular level. N-methyl-D-aspartate receptor 2B (NR2B) subunits in the apical and basal synapses of CA1 pyramidal cells showed asymmetrical distribution depending on whether the input from CA3 pyramidal cells originated from the left or the right hemisphere. Although the contribution of hippocampal asymmetry to cognitive functions has not been understood yet, β2-microglobulin knockout (β2m KO) mice showed both cognitive deficits and lack of hippocampal asymmetry. However, β2m KO mice also displayed deficits in the visual nerve activity-dependent refinement at the developing lateral geniculate nucleus. Therefore, this abnormal visual nerve refinement may have caused visual impairments and, consequently, cognitive deficits in β2m KO mice. Indeed, many rodent cognitive tasks rely on visuospatial cues. To evaluate the visual ability of β2m KO mice precisely, we focused on two different visual components, namely their grating acuity and brightness perception. Then, we compared the performances of β2m KO and C57BL/6J wild-type (WT) mice on two psychophysical tasks: the stripe discrimination task for grating acuity, and the brightness discrimination task for brightness perception. Our findings indicated that although the results of the brightness discrimination task contains indefinite points, the results of the grating acuity test are comparable between β2m KO and WT mice. Therefore, the cognitive deficits that previous studies reported were not caused by a difference of grating acuity between the two strains, but rather by the lack of hippocampal asymmetry in β2m KO mice.</p>

Journal

Keywords

Details 詳細情報について

Report a problem

Back to top