Effect of the 5-HT1A receptor antagonist, (−)-penbutolol, as compared with the β-AR antagonists, (−)-metaprolol and ICI 118,551, on the anxiolytic activity of S 15535 in the rat Geller-Seifter conflict test
| First Injection | Second Injection | Responses/min during Reward | Vehicle/vehicle | Responses/min during Time-Out | Vehicle/vehicle | Responses/min during Conflict | Vehicle/vehicle | n |
|---|---|---|---|---|---|---|---|---|
| % | % | % | ||||||
| Vehicle | Vehicle | 29.2 ± 2.1 | – | 1.9 ± 0.4 | – | 1.0 ± 0.3 | – | 11 |
| Vehicle | S 15535 (1.0) | 30.0 ± 4.2 | 103 | 4.5 ± 1.2 | 237 | 5.4 ± 1.5 | 540 | 11 |
| (−)-Penbutolol (8.0) | Vehicle | 25.3 ± 2.5 | 90 | 1.3 ± 0.5 | 68 | 1.0 ± 0.3 | 100 | 10 |
| (−)-Penbutolol (8.0) | S 15535 (1.0) | 26.5 ± 2.6 | 91 | 3.4 ± 1.0 | 179 | 1.8 ± 0.5* | 180 | 11 |
| Vehicle | Vehicle | 26.3 ± 2.6 | – | 1.2 ± 0.4 | – | 0.7 ± 0.2 | – | 8 |
| Vehicle | S 15535 (1.0) | 32.4 ± 6.8 | 123 | 2.1 ± 0.7 | 175 | 6.0 ± 1.4* | 857 | 8 |
| Metaprolol (4.0)+ | Vehicle | 30.5 ± 4.7 | 116 | 1.3 ± 0.4 | 108 | 2.2 ± 0.5 | 314 | 8 |
| ICI 118,551 (4.0) | ||||||||
| Metaprolol (4.0)+ | S 15535 (1.0) | 29.2 ± 5.3 | 111 | 2.5 ± 0.8 | 208 | 7.2 ± 2.2 | 1029 | 8 |
| ICI 118,551 (4.0) |
First and second injections refer to the successive treatments received by the animals. Doses are in parentheses (mg/kg s.c.). Data are means ± S.E.M. Asterisks indicate significance of differences to vehicle + S 15535 with the Student’s t test, with P ≤ .05. Analysis (ANOVA) of data obtained in the Conflict Period were: Interaction, (−)-penbutolol and S 15535: Effect of S 15535,F(1,39) = 10.1, P < .01; Effect of (−)-penbutolol,F(1,39) = 4.3, P < .05 and Interaction,F(3,36) = 4.4, P < .05. Interaction, Metaprolol + ICI 118,551 and S 15535: Effect of S 15535, F(1,28) = 15.1, P < .001; Effect of (−)-metaprolol + ICI 118,551,F(1,28) = 1.1, P > .05 and InteractionF(1,28) = 0.01, P > .05.