Phencyclidine-induced head-weaving and head-twitch through interaction with 5-HT1 and 5-HT2 receptors in reserpinized rats.
K Yamaguchi, Toshitaka Nabeshima, K Ishikawa, S Yoshida, T Kameyama
Neuropharmacology October 1987 DOI: 10.1016/0028-3908(87)90168-7 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Animal experimental study Peer reviewed |
|---|---|
| Population | Rats, including vehicle-pretreated and reserpine-pretreated groups |
| Interventions | Phencyclidine Ritanserin Pindolol Reserpine Imipramine Mianserin |
| Dose | Phencyclidine 5-7.5 mg/kg (head-weaving), 7.5-12.5 mg/kg (head-twitches), 2.5 mg/kg, 5 mg/kg, 1.25 mg/kg; ritanserin 1 mg/kg; pindolol 20 mg/kg s.c. |
| Measures | head-weaving, head-twitches, 5-HT utilization, [3H]5-HT binding sites, [3H]ketanserin binding sites |
| Key findings | Phencyclidine produced head-weaving at 5-7.5 mg/kg and head-twitches at 7.5-12.5 mg/kg in rats. Ritanserin blocked head-twitches and pindolol blocked head-weaving. Reserpine pretreatment increased serotonin utilization, 5-HT1 and 5-HT2 binding sites, and the intensity of phencyclidine-induced head-weaving and head-twitching. The authors propose that phencyclidine induces head-weaving via 5-HT1 receptors, indirectly after serotonin release, and head-twitch via 5-HT2 receptors, directly or indirectly. |
Abstract
Phencyclidine mainly produced head-weaving and head-twitches at doses of 5-7.5 mg/kg and of 7.5-12.5 mg/kg, respectively. Phencyclidine-induced head-twitches and head-weaving were blocked by pretreatment with ritanserin (1 mg/kg), a selective serotonin (5-HT)2 receptor antagonist and with pindolol (20 mg/kg, s.c.), a 5-HT1 receptor antagonist, respectively. In reserpine-pretreated rats, the degree of utilization of 5-HT and the number of 5-HT1 ([3H]5-HT) and 5-HT2 ([3H]ketanserin) binding sites were significantly increased compared with the figures for the vehicle-pretreated rats. The intensity of phencyclidine-induced head-weaving (at the dose of 2.5 mg/kg) and head-twitch (at the doses of 2.5 and 5 mg/kg) was significantly increased in reserpine-pretreated rats compared with that of vehicle-pretreated rats. Furthermore, in the reserpine-pretreated rats, the intensity of phencyclidine (1.25 mg/kg)-induced head-weaving and head-twitches was increased in combination with imipramine, while the intensity of phencyclidine (2.5 mg/kg)-induced head-weaving and head-twitch was decreased by pretreatment with mianserin, a non-selective 5-HT receptor antagonist. These results indicate that phencyclidine induced head-weaving by interacting with 5-HT1 receptors, indirectly after the release of 5-HT and/or with some other mechanisms and induced head-twitch by interacting with 5-HT2 receptors directly and/or indirectly.