Figure 2

Anxiety-related behavioral tests of wild-type (+/+), heterozygote (+/−), and homozygous mutant mice (−/−). (A and B) An open-field test for a total of 5 min shows significant differences in path length (A) and locomotion time (B) in −/−mice (P < 0.05 and P < 0.01, respectively). +/+, n = 14; +/−, n = 22; −/−, n = 20. (C) Criteria for center vs. border. The center was defined as the inner 16 squares (C, Upper Left). An example of walking paths of a +/+ mouse (Upper Right), a +/− mouse (Bottom Left), and a −/− mouse (Bottom Right) in open-field tests. (D) Percentage of the time spent in the center for a total of 5 min in the open-field test shows a significant difference in −/− mice (P < 0.05). +/+, n = 14; +/−, n = 22; −/−, n = 20. (E) Elevated plus-maze test. Open columns, time spent on open arms; filled columns, time spent on closed arms. No statistically significant difference was observed among the genotypes. +/+, n = 15; +/−, n = 18; −/−, n = 19. (F) Startle responses against various intensities of sound pulses. Stimuli with 105 dB (open columns), 115 dB (gray columns), and 117 dB (filled columns) were given. No statistically significant difference was observed among the genotypes. +/+, n = 8; +/−, n = 10; −/−, n = 15.