Effects of low-doses of methamphetamine on d-fenfluramine-induced head-twitch response (HTR) in mice during ageing and c-fos expression in the prefrontal cortex.
The head-twitch response (HTR) in mice is considered a behavioral model for hallucinogens and serotonin 5-HT EMD 281014 (0.001-0.05 mgkg) or MA (0.1-5 mgkg) blocked d-fenfluramine-induced HTR dose-dependently during ageing. The 5-HT EMD 281014 suppressed d-fenfluramine-induced HTR but failed to prevent d-fenfluramine-evoked c-fos expression which suggest involvement of additional serotonergic receptors in the mediation of evoked c-fos. The suppressive effect of MA on d-fenfluramine-evoked HTR is due to well-recognized functional interactions between stimulatory 5-HT