Table 1.
General physical characteristics and sensory/motor functions of M1R−/− mice and their wild-type littermates
| +/+ | −/− | |
|---|---|---|
| Physical characteristics | ||
| Weight (grams) | 32.7 (±0.9) | 29.5 (±0.6) |
| Whiskers (% with) | 62 | 88 |
| Fur (% with normal fur) | 86 | 100 |
| Rectal temperature (°C) | 37.1 (±0.2) | 37.3 (±0.1) |
| Sensory motor reflex | ||
| Eye blink (% with normal response) | 100 | 100 |
| Ear twitch (% with quick response) | 86 | 96 |
| Whisker twitch (% with normal response) | 81 | 96 |
| Righting reflex (% with normal response) | 100 | 100 |
| Acoustic startle response (arbitrary unit) | ||
| Stimulus intensity = 110 dB | 176 (±36) | 211 (±38) |
| Stimulus intensity = 120 dB | 360 (±60) | 508 (±50) |
| Prepulse inhibition (%; startle stimulus = 120 dB) | ||
| Prepulse intensity = 74 dB | 55 (±5) | 47 (±4) |
| Prepulse intensity = 78 dB | 70 (±4) | 74 (±5) |
| Pain test | ||
| Hot plate (latency; seconds) | 7.4 (±0.6) | 8.1 (±0.5) |
| Motor tests | ||
| Wire hang (latency to fall; seconds) | 32.5 (±5.0) | 35.2 (±4.5) |
| Rotarod (latency to fall; seconds; average of three trials) | ||
| Day 1 | 104 (±14) | 87 (±9) |
| Day 2 | 153 (±17) | 165 (±15) |
Data represent the mean (±SEM) (M1R−/−mice, n = 25; wild-type mice, n = 21).