Subchronic nandrolone administration reduces cocaine-induced dopamine and 5-hydroxytryptamine outflow in the rat nucleus accumbens.
BACKGROUND
The abuse of anabolic androgenic steroids (AASs) is not only a problem in the world of sports but is associated with the polydrug use of nonathletes. Investigations of the neurochemical effects of AAS have focused in part on the monoaminergic systems, involving, among other things, the development of dependence. We have previously shown that pretreatment with nandrolone decanoate attenuates dose-dependently the increase in extracellular dopamine (DA) concentration evoked by amphetamine and 3,4-methylenedioyxymethamphetamine in the nucleus accumbens (NAc).


OBJECTIVE
The aim of this study was to investigate whether the nandrolone pre-exposure modulates the acute neurochemical and behavioral effects of cocaine in rats and whether the effects are long lasting.


METHODS
DA, 5-hydroxytryptamine (5-HT), and their metabolites were measured from samples collected from the NAc by microdialysis. The behavior of the animals was recorded.


RESULTS
The present study demonstrates that five injections of nandrolone (5 and 20 mg/kg) inhibited cocaine-evoked DA and 5-HT outflow in the NAc, locomotor activity (LMA), and stereotyped behavior in experimental animals, and that these effects are seen even after elimination of nandrolone from bloodstream.


CONCLUSIONS
Given that accumbal outflow of DA and 5-HT, as well as LMA and stereotyped behavior, is related to gratification of stimulant drugs, this study suggests that nandrolone, at the doses tested, has a significant effect on the pleasurable properties of cocaine. Furthermore, because neurochemical and behavioral responses were still attenuated after a fairly long recovery period, it seems that nandrolone may induce long-lasting changes in the brains of rat.
Kurling-Kailanto
Sanna
S
Department of Alcohol, Drugs and Addiction, National Institute for Health and Welfare, P.O. Box 30, 00271, Helsinki, Finland. sanna.kailanto@thl.fi
Kankaanpää
Aino
A
Seppälä
Timo
T
D045930:Anabolic Agents / Q000097:blood / Q000494:pharmacology*; D000818:Animals; D003042:Cocaine / Q000037:antagonists & inhibitors* / Q000493:pharmacokinetics / Q000494:pharmacology; D004298:Dopamine / Q000378:metabolism*; D018765:Dopamine Uptake Inhibitors / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D008297:Male; D009043:Motor Activity / Q000187:drug effects; D009277:Nandrolone / Q000008:administration & dosage / Q000097:blood / Q000494:pharmacology*; D009714:Nucleus Accumbens / Q000187:drug effects* / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D012701:Serotonin / Q000378:metabolism*; D013239:Stereotyped Behavior / Q000187:drug effects; D013997:Time Factors
D045930:Anabolic Agents; D018765:Dopamine Uptake Inhibitors; D012701:Serotonin; D009277:Nandrolone; D003042:Cocaine; D004298:Dopamine