Contrasting actions of acute or chronic paroxetine and fluvoxamine on morphine withdrawal-induced place conditioning.
The acute and chronic effects of paroxetine and fluvoxamine on naloxone withdrawal-induced place aversion in morphine dependent rats were investigated. Acutely administered fluvoxamine (25 mg/kg s.c. given 30 min prior to naloxone withdrawal pairing) and chronic daily paroxetine (10 mg/kg s.c.) coadministration with a morphine induction protocol, both attenuated morphine withdrawal place aversion. Conversely, acutely administered paroxetine (up to 25 mg/kg s.c.) or chronic daily fluvoxamine (10 mg/kg s.c.) coadministration with morphine did not modify subsequent withdrawal place aversion. Previous radioligand binding studies indicate that fluvoxamine has opioid-displacing properties. It is suggested therefore that acute fluvoxamine may have decreased withdrawal aversion, probably through serotonin and also, in part, via an opioid-like mechanism whereas chronic paroxetine decreased withdrawal aversion by a serotonergic mechanism, but it is not clear whether opioid systems play any role in the action of paroxetine.
Rafieian-Kopaei
M
M
Welsh School of Pharmacy, UWCC, Cardiff, UK.
Gray
A M
AM
Spencer
P S
PS
Sewell
R D
RD
D000704:Analysis of Variance; D000818:Animals; D003213:Conditioning, Psychological / Q000187:drug effects*; D004195:Disease Models, Animal; D004334:Drug Administration Schedule; D016666:Fluvoxamine / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D007279:Injections, Subcutaneous; D008297:Male; D009020:Morphine / Q000633:toxicity*; D009270:Naloxone / Q000378:metabolism; D017374:Paroxetine / Q000008:administration & dosage / Q000494:pharmacology* / Q000627:therapeutic use; D051381:Rats; D017207:Rats, Sprague-Dawley; D012701:Serotonin / Q000378:metabolism; D017367:Selective Serotonin Reuptake Inhibitors; D013375:Substance Withdrawal Syndrome / Q000188:drug therapy*; D019966:Substance-Related Disorders
D016666:Fluvoxamine; D009020:Morphine; D009270:Naloxone; D017374:Paroxetine; D012701:Serotonin; D017367:Selective Serotonin Reuptake Inhibitors