Differential behavioral outcomes of 3,4-methylenedioxymethamphetamine (MDMA-ecstasy) in anxiety-like responses in mice
V. Ferraz-de-paula, D. Stankevicius, A. Ribeiro, M.l. Pinheiro, E.c. Rodrigues-costa, J.c. Florio, S.f. Lapachinske, R.l.m. Moreau, J. Palermo-neto
Brazilian Journal of Medical and Biological Research September 4, 2013 Peer reviewed DOI: 10.1590/s0100-879x2011000500008 via DOAJ
Summary
MDMA treatment in 2-month-old Balb/c male mice at a dose of 10 mg/kg led to increased distance traveled and time spent moving in an open field, decreased exploratory activity in the hole board, and increased exploration in the elevated plus maze. Additionally, there were increased serum corticosterone levels and striatal dopamine turnover. Overall, these findings suggest an anxiogenic-like effect of acute MDMA treatment, although behavioral anxiety expression was impaired due to its motor stimulating effects.
Study at a glance
| Sample size | 70 |
|---|---|
| Population | 2-month-old Balb/c male mice |
| Key finding | MDMA at 10 mg/kg induced anxiogenic-like effects alongside motor stimulation in behavioral tests. |
Abstract
Anxiolytic and anxiogenic-like behavioral outcomes have been reported for methylenedioxymethamphetamine (MDMA or ecstasy) in rodents. In the present experiment, we attempted to identify behavioral, hormonal and neurochemical outcomes of MDMA treatment to clarify its effects on anxiety-related responses in 2-month-old Balb/c male mice (25-35 g; N = 7-10 mice/group). The behavioral tests used were open field, elevated plus maze, hole board, and defensive behavior against predator odor. Moreover, we also determined striatal dopamine and dopamine turnover, and serum corticosterone levels. MDMA was injected ip at 0.2, 1.0, 5.0, 8.0, 10, or 20 mg/kg. MDMA at 10 mg/kg induced the following significant (P < 0.05) effects: a) a dose-dependent increase in the distance traveled and in the time spent moving in the open field; b) decreased exploratory activity in the hole board as measured by number of head dips and time spent in head dipping; c) increased number of open arm entries and increased time spent in open arm exploration in the elevated plus maze; d) increased time spent away from an aversive stimulus and decreased number of risk assessments in an aversive odor chamber; e) increased serum corticosterone levels, and f) increased striatal dopamine level and turnover. Taken together, these data suggest an anxiogenic-like effect of acute MDMA treatment, despite the fact that behavioral anxiety expression was impaired in some of the behavioral tests used as a consequence of the motor stimulating effects of MDMA.