MDMA produces a conditioned place preference and elicits ejaculation in male rats: a modulatory role for the endogenous opioids.
Methylenedioxymethamphetamine (MDMA) can produce a conditioned place preference (CPP) among rats. The ability of MDMA to produce a CPP was assessed while some rats were under the influence of naltrexone, 56 mg/kg, given 4 h before conditioning. Naltrexone attenuated MDMA's ability to produce a CPP without completely blocking MDMA's effects. Having noticed previously the production of seminal plugs by rats receiving MDMA, the presence of seminal plugs was recorded across the 8 days of conditioning. Roughly half of the rats receiving 6.3 mg/kg of MDMA left plugs during the conditioning period, while over two-thirds of those receiving a combination of MDMA and naltrexone left plugs. A second study, assessing further doses of MDMA, tabulated the drug's effects on the production of seminal plugs across 3 h. Besides eliciting ejaculation, MDMA also led to increased urination and defecation and a loss of body weight. These results support suggestions that the endogenous opioids modulate the reinforcing properties of stimulant drugs and affect male sexuality.
Bilsky
E J
EJ
Department of Psychology, Rensselaer Polytechnic Institute, Troy, NY 12180.
Hubbell
C L
CL
Delconte
J D
JD
Reid
L D
LD
D015104:3,4-Methylenedioxyamphetamine / Q000031:analogs & derivatives* / Q000494:pharmacology; D000818:Animals; D003216:Conditioning, Operant / Q000187:drug effects*; D003672:Defecation / Q000187:drug effects; D004542:Ejaculation / Q000187:drug effects*; D004723:Endorphins / Q000502:physiology*; D008297:Male; D018817:N-Methyl-3,4-methylenedioxyamphetamine; D009271:Naltrexone / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D012702:Serotonin Antagonists / Q000494:pharmacology; D014326:Tropanes / Q000494:pharmacology; D014554:Urination / Q000187:drug effects
D004723:Endorphins; D012702:Serotonin Antagonists; D014326:Tropanes; D015104:3,4-Methylenedioxyamphetamine; D009271:Naltrexone; D018817:N-Methyl-3,4-methylenedioxyamphetamine; C042253:bemesetron