Acute concomitant effects of MDMA binge dosing on extracellular 5-HT, locomotion and body temperature and the long-term effect on novel object discrimination in rats

Abstract

MDMA-induced 5-HT release in the brain was not responsible for either the hyperthermia or increased locomotor activity that occurred. Since neither dose schedule of MDMA induced a neurotoxic loss of brain 5-HT 2 weeks after its administration, the impairment of recognition memory found in novel object discrimination probably results from other long-term changes yet to be established.

Contribution of serotonin and dopamine to changes in core body temperature and locomotor activity in rats following repeated administration of mephedrone

“…Importantly, the total ambulatory activity counts following the second and third injections of mephedrone were comparable to those following the first injection. This response therefore differs markedly from MDMA where progressively increasing hyperactivity was observed following a similar repeated dosing schedule (Rodsiri et al, 2011). …”

“…Radiotelemetry was conducted as previously described (Rodsiri et al, 2011 minute epochs and expressed as mean ± standard error of the mean (SEM) activity counts.…”

“…As our Animals (Scientific Procedures) Act, 1986 project licence did not permit radiotelemetry and microdialysis to be performed in the same animal, microdialysis was measured in a separate cohort of rats using an identical protocol as previously described (Rodsiri et al, 2011 …”

“…The current repeat dosing studies used continuous radiotelemetry to accurately and repeatedly record locomotor activity and core body temperature over a prolonged period in the same animal, without repeated insertion of a rectal probe, which would confound assessment of activity, at a consistent dose interval to previous preclinical studies using MDMA or mephedrone (Baumann et al, 2012;Baumann et al, 2008;Rodsiri et al, 2011).…”

Genetic Deletion of Trace Amine 1 Receptors Reveals Their Role in Auto-Inhibiting the Actions of Ecstasy (MDMA)

“…Reinforcement of the hyperthermic actions of MDMA in TA 1 -KO mice MDMA exerts a complex influence upon core temperature (Green et al, 2003;Rodsiri et al, 2011) and elicited a biphasic time-and dose-dependent hypothermia-hyperthermia in WT mice, which was transformed into a monophasic, rapid, and dose-dependent hyperthermia in TA 1 -KO counterparts. Increasing ambient temperature favors hyperthermia (Green et al, 2003;Feduccia et al, 2010) and exaggerated the hyperthermic response to MDMA in TA 1 -KO mice, consistent with the hypothermic impact of TA 1 R activation (Scanlan et al, 2004;Hart et al, 2006).…”