Paradoxical effects of serotonin and opioids in pemoline-induced self-injurious behavior.
Self-injurious behavior (SIB) is a symptom of various psychiatric disorders with differing etiologies. Although no generally effective pharmacological treatment of SIB is available, subsets of individuals exhibiting SIB have been found to respond to opioid antagonists and selective serotonin reuptake inhibitors (SSRIs). The present study evaluated the efficacy of these two treatments in the pemoline-induced model of self-biting behavior (SBB) in rats. Using a factorial design, adult rats receiving daily pemoline at 100 mg/kg or the peanut oil vehicle were pretreated with either distilled water vehicle (1 cc/kg), naltrexone (1 mg/kg), or paroxetine (1 mg/kg). Each day, animals were rated on the severity of SBB and also periodically behavioral changes were evaluated using various other outcome measures. Paroxetine significantly increased the severity of SBB induced by pemoline, while naltrexone only marginally increased the SBB. These results were not expected and suggest that further studies into the role of serotonin agonists and antagonists are needed in evaluating this model.
Turner
C
C
Department of Psychology, Bowling Green State Univ., OH 43402, USA.
Panksepp
J
J
Bekkedal
M
M
Borkowski
C
C
Burgdorf
J
J
D000661:Amphetamine / Q000037:antagonists & inhibitors / Q000494:pharmacology; D000818:Animals; D000697:Central Nervous System Stimulants / Q000494:pharmacology*; D004357:Drug Synergism; D008297:Male; D009043:Motor Activity / Q000187:drug effects; D009271:Naltrexone / Q000494:pharmacology; D009292:Narcotic Antagonists / Q000494:pharmacology*; D017374:Paroxetine / Q000494:pharmacology; D010389:Pemoline / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013216:Reflex, Startle / Q000187:drug effects; D016728:Self-Injurious Behavior / Q000139:chemically induced* / Q000523:psychology; D017367:Selective Serotonin Reuptake Inhibitors / Q000494:pharmacology*; D012919:Social Behavior; D013997:Time Factors
D000661:Amphetamine; D000697:Central Nervous System Stimulants; D009271:Naltrexone; D009292:Narcotic Antagonists; D017374:Paroxetine; D010389:Pemoline; D017367:Selective Serotonin Reuptake Inhibitors