THE EFFECT OF THE REPEATED ADMINISTRATION OF THE COMPOUND 3,4-METHYLENEDIOXYMETHAMPHETAMINE ON THE RESPONSE OF RATS TO THE 5-HT2A,C RECEPTOR AGONIST (+ -)-1-(2,5-DIMETHOXY-4-IODOPHENYL)-2-AMINOPROPANE (DOI)/

In this study, we examined the effect of the 5-HT2A,C receptor agonist (+/-)-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI) on locomotor activity and the head twitch response in rats by the repeated (twice d aily for il days) subcutaneous administration of 0.9% saline (1 ml/kg) or (+/-)-3,4-Methylenedioxymethamphetamine (MDMA) (20 mg/kg), a compo und that selectively destroys serotonergic nerve terminals. There was no difference between the MDMA- and saline-treated rats regarding the (+/-)-DOI-induced (0.625, 1.25 or 2.5 mg/kg, i.p.) increase and decrea se in the head twitch response and horizontal locomotor activity, resp ectively. Overall, repeated MDMA does not alter the behavioral respons e of rats to (+/-)-DOI.