Fyn-deficient mice produced by inserting the β-galactosidase gene (lacZ) into the fyn gene locus were tested in a radial maze, an open field and an elevated plus-maze. In the radial maze, the homozygous Fyn-deficient (fyn(z)/fyn(z)) mice showed no impairment in spatial learning, although they showed a stronger avoidance tendency for those arms located closer to the experimenter during pretraining (adaptation). In the open-field test, the fyn(z)/fyn(z) mice defecated more frequently in the bright condition than did the +/fyn(z) mice, and they were less active during the first 10-min test period than the +/fyn(z) mice. In addition, the temporal pattern of locomotor activity for fyn(z)/fyn(z) mice was altered by changing the illumination while the pattern for +/fyn(z) mice remained relatively unchanged. Scores reflecting the fear-response in the elevated plus-maze were higher in the fyn(z)/fyn(z) mice. These results indicate that Fyn deficiency increased fear-response, but did not impair spatial learning in the radial maze. It is suggested that we should take account of effects of emotional factors in the learning experiment using mutant mice.
All Science Journal Classification (ASJC) codes
- Molecular Biology
- Cellular and Molecular Neuroscience