Heat increases MDMA-enhanced NAcc 5-HT and body temperature, but not MDMA self-administration.
There is a concern that hot environments enhance adverse effects of 3,4-methylenedioxymethamphetamine (MDMA or "Ecstasy"). In this study, long-term (4-weeks) daily MDMA self-administration sessions and an MDMA Challenge test were conducted with rats under normal and high thermal conditions (23° or 32°C). During MDMA self-administration sessions, activity and body temperature were increased by heat or MDMA experience, while MDMA self-administration rates increased with experience, but were comparable between thermal conditions. At the MDMA Challenge test (3.0 mg/kg, i.v.), in vivo microdialysis showed that nucleus accumbens serotonin (NAcc 5-HT) and dopamine (DA) responses were significantly increased in both thermal conditions. In the heated environment, MDMA-stimulated 5-HT responses and core temperature (but not DA) were significantly greater than at room temperature. Though the heated environment did not acutely boost MDMA intake, exaggerated NAcc 5-HT responses to MDMA may result in 5-HT depletion; a condition associated with Ecstasy use escalation and neural dysfunctions altering mood and cognition.
Feduccia
Allison A
AA
University of Texas at Austin, PHAR-Pharmacology, 1 University Station A1915, Austin, TX 78712-0125, USA. allisonfeduccia@mail.utexas.edu
Kongovi
Nundhun
N
Duvauchelle
Christine L
CL
D000818:Animals; D001831:Body Temperature / Q000187:drug effects / Q000502:physiology*; D003216:Conditioning, Operant / Q000187:drug effects / Q000502:physiology; D006358:Hot Temperature; D008297:Male; D018817:N-Methyl-3,4-methylenedioxyamphetamine / Q000008:administration & dosage*; D009714:Nucleus Accumbens / Q000187:drug effects / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012646:Self Administration; D012701:Serotonin / Q000378:metabolism*
D012701:Serotonin; D018817:N-Methyl-3,4-methylenedioxyamphetamine