3,4-Methylenedioxymethamphetamine and naloxone in rat rotational behaviour and open field.
It has recently been shown that 3,4-Methylenedioxymethamphetamine (MDMA) has an anti-parkinsonian effect in rodent models of Parkinson's disease. The mechanism of this anti-parkinsonian action is unknown. Opioids have been suggested to play a role in MDMA-induced behaviour. We therefore investigated MDMA and naloxone in the rat rotational behavioural model. Male Sprague-Dawley rats were lesioned unilaterally with 6-hydroxydopamine at the medial forebrain bundle. Administration of R/S-MDMA (5 mg/kg, s.c.) produced ipsilateral rotations. Naloxone (2, 5, 10 mg/kg, s.c.) did not produce rotations on its own but reduced the number of MDMA-induced ipsilateral rotations. This effect was not dose-dependent. In contrast to reports on mice, in unlesioned animals, naloxone (10 mg/kg, s.c.) did not block MDMA (5 mg/kg, s.c.)-induced hyperactivity in an open field in our experiment. It is concluded that endogenous opioids play a role in MDMA's action in the rat rotational behavioural model.
Lebsanft
Heike B
HB
Department Neuropharmacology, Zoological Institute, Faculty of Biology, University of Tuebingen, Auf der Morgenstelle 28 E, 72076 Tuebingen, Germany. heike.lebsanft@uni-tuebingen.de
Kovar
Karl-Artur
KA
Schmidt
Werner J
WJ
D000704:Analysis of Variance; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D006213:Hallucinogens / Q000494:pharmacology*; D008297:Male; D009043:Motor Activity / Q000187:drug effects; D018817:N-Methyl-3,4-methylenedioxyamphetamine / Q000494:pharmacology*; D009270:Naloxone / Q000494:pharmacology*; D009292:Narcotic Antagonists / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors
D006213:Hallucinogens; D009292:Narcotic Antagonists; D009270:Naloxone; D018817:N-Methyl-3,4-methylenedioxyamphetamine