Anxiolytic effect of lisuride and its binding to 5-HT1A receptor in rat brain

• Published in: Japanese Journal of Pharmacology 1989, Vol.49 (suppl), p.63-63
• Main Authors: Akai, Tetsuo, Hakada, Yukio, Ikoma, Yukihiro, Yamaguchi, Hotonon, Nakagawa, Hidehiko, Osbino, Nozomu
• Format: Article
• Language: English
• ISSN: 0021-5198; 1347-3506
• DOI: 10.1016/S0021-5198(19)56032-2

In order to clarify the serotonergic effects of lisuride in the brain, binding of lisuride to the 5-HT1A receptors in rat brain, and its effects on the 5-HT behavioral syndrome and water-lick conflict test in rats were investigated. Lisuride strongly inhibited the binding of [3 H]-8-OH-DPAT (5-HT1A agonist) to 5-HT1A receptors in hippocampus membranes. The Ki values for lisuride, 5-HT, 5-MeO-DMT were 0.47, 0.54 and 2.1 nM, respectively. Lisuride (≧0.1 mg/kg, i.p.) induced the 5-HT behavioral syndrome with symptoms such as head weaving, forepaw treading and hindlimb abduction, like 8-OH-DPAT(≧0.5 mg/kg, i.p.) did. Furthermore. lisuride (≧0.05 mg/kg, i.p.) increased the number of shocks in the water-lick conflict test, like diazepam (2.5 mg/kg, i.p.) did. These results show that lisuride acts as a strong agonist on the 5-HT1A receptors in rat brain. Our findings also suggest that lisuride may be a potential anxiolytic, since 5-HT1A receptor sites in the brain were found to be related to anxiolytic effects.