Table 1.
Behavioral Characterization of AMIGO-Deficient Mice
| Test and Parameter | KO vs WT | WT | KO | F Value | P Value |
|---|---|---|---|---|---|
| Elevated plus maze | |||||
| Distance, cm | ↗ | 1154.6±77.7 | 1577.9±133.6 | F(1,22) = 6.81 | .016 |
| Open arm latency, s | 142.5±36 | 69.2±20.33 | ns | ||
| Open entries, % | 21.5±4.5 | 31±3.2 | ns | ||
| Open arm time, s | ↗ | 31.5±7.8 | 57.8±7.9 | F(1,22) = 5.78 | .025 |
| Rearings, s | 20.5±2.7 | 23.3±2.5 | ns | ||
| Open field | |||||
| Distance, cm | ↗ | 4602.3±339.2 | 7279.4±520.3 | F(1,22) = 17.12 | .0004 |
| Distance in center, % | ↗ | 22.6±1.7 | 17.2±1.2 | F(1,22) = 7.61 | .0115 |
| Latency to center, s | 16.5±4.5 | 14.5±4.7 | ns | ||
| Time in center,s | 272.1±30.7 | 223.2±21 | ns | ||
| Center entries, n | ↗ | 410.7±13.4 | 569.6±34.1 | F(1,22) = 16.40 | .0005 |
| Rearing, s | 225.5±26.9 | 273.8±22.4 | ns | ||
| Light–dark | |||||
| Latency to dark, s | 30.8±16.4 | 11±1.8 | ns | ||
| Light–dark transitions, n | 11.4±2 | 15±1.8 | ns | ||
| Distance in light, cm | 977.4±97.1 | 1001.2±119.6 | ns | ||
| Time in light, s | ↘ | 182.2±23.9 | 114.8±11.3 | F(1,22) = 7.21 | .013 |
| Rearing, s | 15.6±3.7 | 13±2.6 | ns | ||
| Y-maze | |||||
| Spontaneous alternation, % | 67.5±4 | 59.5±3.5 | ns | ||
| Hot plate | |||||
| Latency to reaction, s | 15.29±1 | 19.58±3.7 | ns | ||
| Rota-Rod | |||||
| Latency to fall, first trial, s | 83.8±21.6 | 86.5±17.9 | ns | ||
| Latency to fall, last trial, s | 205.9±27.3 | 239.7±25.4 | ns | ||
| Beam walking test | |||||
| Time to fall 1st trial, s | 94.1±10 | 98.5±11.8 | ns | ||
| Time to fall 2nd trial, s | 97.2±10.2 | 92.4±12.5 | ns | ||
| Crossed marks 1st trial, n | 36.3±7.6 | 26.7±7.9 | ns | ||
| Crossed marks 2nd trial, n | 36.8±6.1 | 21±5.2 | ns | ||
| Startle response | ↘ | 1611.9±183.3 | 691.6±106.9 | F(1,45) = 16.61 | .0002 |
| Prepulse inhibition | |||||
| PPI 68 dB | ↘ | 43.7±3.6 | 30.8±3.8 | F(1,45) = 6.07 | .0176 |
| PPI 72 dB | ↘ | 49.6±3.2 | 35.8±3.2 | F(1,45) = 9.23 | .0039 |
| PPI 76 dB | ↘ | 52.4±3.8 | 40.3±3.8 | F(1,45) = 4.98 | .0307 |
| PPI 80 dB | ↘ | 58.7±3.1 | 38.2±5 | F(1,45) = 13.14 | .0007 |
| Forced swim test | |||||
| Immobility time, s | 73.5±15.4 | 97.5±10.5 | ns | ||
| Tube test | |||||
| Wins, % | ↘ | 73.1±8.3 | 24.9±5.1 | F(1,23) = 23.55 | .0001 |
| Resident-intruder test | |||||
| Time in social activity, % | 42.3±4.3 | 34.1±3.9 | ns | ||
| Time in nonsocial activity, % | 12.0±2.8 | 10.2±1.4 | ns | ||
| IntelliCage | |||||
| Corner visits, n | 663.2±65.8 | 733.3±71 | ns | ||
| Corner visits with drinking, % | 0.309±0.019 | 0.276±0.038 | ns | ||
| Drinking, n | 751.3±58.5 | 854.4±55.7 | ns | ||
| Corner visits for 30min, n | 7.3±4.6 | 5.7±2 | ns | ||
| Corner visits till first darkness. n | 29.7±10.6 | 35.4±14.2 | ns | ||
| Latency to first visit, s | 2328.5±1205.5 | 17461.7±11169.6 | ns | ||
| Latency to all 4 corner visits, s | 7526.7±4077.6 | 25020.2±16.852.8 | ns | ||
| Latency to drinking, s | 55432.9±21857.2 | 34910.4±15741.3 | ns | ||
| Spontaneous alteration, % | 13.3±4.1 | 13.8±7.6 | ns | ||
| Place learning | 38.8±0.8 | 40.4±1.7 | ns | ||
| Patrolling | ↘ | 41.1±0.9 | 35.9±1.1 | F(1,11) = 13.38 | .0038 |
Note: ↗ increased in the KO mice; ↘ decreased in the KO mice; KO, knockout; ns, statistically not significant; PPI, prepulse inhibition; WT, wild-type. Nociception (Hot plate) and motor coordination (Rota-Rod, Beam walking test) of the AMIGO KO mice were normal. Several tests (Elevated plus maze, Open field, Prepulse inhibition, Tube test, Patrolling in IntelliCage) detected abnormalities in schizophrenia-related behavioral domains. From the 2 tests modeling anxiety-related behavior, the light/dark test suggested that the AMIGO KO mice are more anxious. However, the elevated plus maze suggested that the AMIGO KO mice are less anxious. The discrepancy between these 2 tests may be due to the hyperactivity of the AMIGO KO mice and dependency of the used tests on general locomotor activity. Values are presented as mean ± SEM.