Phencyclidine-induced head-twitch responses as 5-HT2 receptor-mediated behavior in rats.
Neuroscience letters – May 19, 1987
Source: PubMed
Summary
Ritanserin completely blocked phencyclidine (PCP)-induced head-twitch in both mice and rats, with a dosage of 1 mg/kg effectively countering doses of PCP at 7.5, 10, and 12.5 mg/kg. Additionally, 5-methoxy-N,N-dimethyltryptamine (5-MeODMT) also triggered head-twitch, which was inhibited by ritanserin at 2 and 4 mg/kg in mice. Interestingly, while both drugs caused head-weaving in mice post-ritanserin treatment, this behavior was absent in rats, indicating distinct receptor involvement: 5-HT2 for PCP and 5-HT1 for 5-MeODMT in rats.
Abstract
This study was designed to assess whether phencyclidine (PCP)-induced head-twitch was antagonized by ritanserin, a selective serotonin (5-HT2) receptor antagonist, in mice and rats to confirm the involvement of 5-hydroxytryptamine (5-HT) neurons in PCP actions in comparison with 5-methoxy-N,N-dimethyltryptamine (5-MeODMT)-induced behavior. PCP (7.5, 10 and 12.5 mg/kg, i.p.)-induced head-twitch was completely antagonized by ritanserin (1 mg/kg, s.c.) in mice and rats, and 5-MeODMT (2 and 4 mg/kg, i.p.)-induced head-twitch was also completely antagonized by ritanserin in mice. PCP and 5-MeODMT induced head-weaving in mice after ritanserin treatment, but this did not occur in rats. In rats, 5-MeODMT failed to induce head-twitch. These results suggest that PCP-induced head-twitch response in rats is developed via 5-HT2 receptors and it is a useful 5-HT2 receptor model, while 5-MeODMT-induced head-weaving in rats is developed via 5-HT1 receptors and is a useful 5-HT1 receptor model.