A behavioral and neuroanatomical assessment of an inbred substrain of 129 mice with behavioral comparisons to C57BL/6J mice.
The inbred 129 substrains have been characterized as poor learners that display hypoplasia of the corpus callosum. However, they are used extensively as a source of embryonic stem (ES) cells for creating mice carrying altered copies of a targeted gene ('knockout mice'). The present research investigated callosal agenesis and behavior in the 129/SvEvTac substrain and compared their behavior to that of C57BL/6J mice. In addition, the degree to which callosal agenesis affected behavior was assessed. Nearly 80% of 129/SvEvTac mice in the current sample exhibited callosal hypoplasia, although this was not subsequently found to be associated with any measure of cognition. They learned the Morris maze and a non-spatial pattern discrimination task, though at a level inferior to C57BL/6J mice. They were unable to learn shuttlebox avoidance or the Lashley III maze. The only measure on which they performed better than C57BL/6J mice was a simple water escape task. Thus, 129/SvEvTac mice, in addition to displaying aberrant neuroanatomy, perform poorly on many behavioral tasks, resulting in potential interpretational difficulties.
Balogh
S A
SA
Biobehavioral Sciences Graduate Degree Program, University of Connecticut, U-154, 3107 Horsebarn Hill Road, Storrs, CT 06269-4154, USA.
McDowell
C S
CS
Stavnezer
A J
AJ
Denenberg
V H
VH
D061085:Agenesis of Corpus Callosum; D000818:Animals; D001362:Avoidance Learning / Q000502:physiology; D005069:Evaluation Studies as Topic; D007858:Learning / Q000502:physiology*; D018782:Maze Learning / Q000502:physiology; D051379:Mice; D008810:Mice, Inbred C57BL; D013045:Species Specificity; D013234:Stem Cells / Q000502:physiology*