Clozapine and haloperidol effects on the basal startle response and prepulse inhibition of startle disrupted by MK-801, DOI, and d-amphetamine in Sprague-Dawley rats and the naturally low PPI in DBA/2N mice
Data are expressed as the mean basal startle and the mean percentage of prepulse inhibition. The values in parentheses are the S.E.M. (n = 8-20 subjects per group).
Clozapine (mg/kg i.p.) | Basal Startle | % PPI |
|---|---|---|
| MK-801 (0.5 mg/kg i.p.) | ||
| Veh/Veh | 62.3 (14.8)* | 69.1 (3.0)* |
| Veh/MK-801 | 335.7 (46.2) | 25.5 (7.6) |
| 3 Cloz/MK-801 | 226.3 (45.7)* | 34.2 (3.7) |
| 5.4 Cloz/MK-801 | 170.3 (33.3)* | 43.4 (4.3)* |
| 10 Cloz/MK-801 | 138.8 (21.1)* | 31.3 (5.2) |
| DOI (3 mg/kg s.c.) | ||
| Veh/Veh | 70.8 (6.9) | 72.5 (4.5)* |
| Veh/DOI | 71.7 (24.7) | 56.3 (3.8) |
| 3 Cloz/DOI | 82.8 (15.1) | 59.5 (2.1) |
| 5.4 Cloz/DOI | 47.0 (6.9) | 68.3 (5.0)* |
| 10 Cloz/DOI | 53.8 (12.3) | 68.8 (3.6)* |
| AMPH (4 mg/kg s.c.) | ||
| Veh/Veh | 78.4 (7.3) | 78.2 (2.9)* |
| Veh/AMPH | 133.9 (23.2) | 55.3 (4.3) |
| 3 Cloz/AMPH | 145.8 (36.9) | 57.3 (5.0) |
| 5.4 Cloz/AMPH | 110.5 (13.1) | 50.3 (5.1) |
| 10 Cloz /AMPH | 118.6 (28.6) | 68.5 (4.0)* |
| DBA/2N | ||
| Veh | 55.5 (7.3) | 14.3 (7.1) |
| 0.5 Cloz | 60.0 (10.5) | 12.1 (7.2) |
| 1 Cloz | 70.4 (13.9) | 6.2 (7.6) |
| 5 Cloz | 21.1 (7.0)* | 5.3 (5.4) |
| Haloperidol (mg/kg i.p.) | Basal Startle | % PPI |
| MK-801 (0.5 mg/kg i.p.) | ||
| Veh/Veh | 58.1 (5.1)* | 71.8 (3.0)* |
| Veh/MK-801 | 295.2 (59.5) | 10.1 (8.2) |
| 0.3 hal/MK-801 | 187.1 (33.0)* | 22.9 (6.8) |
| 1 hal/MK-801 | 134.8 (12.6)* | 9.0 (7.0) |
| 3 hal/MK-801 | 202.4 (31.9) | 19.3 (3.0) |
| DOI (3 mg/kg s.c.) | ||
| Veh/Veh | 52.2 (5.8) | 74.3 (3.0)* |
| Veh/DOI | 58.0 (16.2) | 47.1 (3.7) |
| 0.3 hal/DOI | 51.9 (16.3) | 50.5 (8.0) |
| 1 hal/DOI | 46.6 (10.2) | 59.3 (5.9) |
| 3 hal/DOI | 29.5 (7.5) | 58.7 (8.0) |
| AMPH (4 mg/kg s.c.) | ||
| Veh/Veh | 81.9 (13.9)* | 75.1 (4.0)* |
| Veh/AMPH | 127.6 (19.7) | 58.6 (5.8) |
| 0.3 hal/AMPH | 84.2 (15.7)* | 73.2 (1.6)* |
| 1 hal/AMPH | 67.3 (14.1)* | 78.1 (2.7)* |
| 3 hal/AMPH | 41.8 (7.8)* | 72.2 (2.6)* |
| DBA/2N | ||
| Veh | 76.7 (5.4) | 11.3 (3.9) |
| 1 hal | 75.4 (16.4) | 35.1 (2.9)* |
| 3 hal | 58.9 (12.0) | 31.5 (4.1)* |
| 5 hal | 19.8 (4.2)* | 30.2 (6.2)* |
Veh, vehicle; cloz, clozapine; hal, haloperidol; AMPH, d-amphetamine.
↵* Significantly different from the disrupting agent in rats and vehicle treatment in DBA/N2 mice.