Naltrexone Selectively Elevates GABAergic Neuroactive Steroid Levels in Heavy Drinkers With the ASP40 Allele of the OPRM1 Gene: A Pilot Investigation Journal Article uri icon



  • Background:  Preclinical studies have implicated GABAergic neurosteroids in behavioral responses to alcohol. Naltrexone is thought to blunt the reinforcing effects of alcohol, and a few studies have found that the effects of naltrexone are moderated by the Asn40Asp polymorphisms of the OPRM1 gene. The present study seeks to integrate these lines of research by testing (i) the moderating role of the functional Asn40Asp polymorphism of the OPRM1 gene on naltrexone‐induced alternations in GABAergic neurosteroid levels, namely (3α,5α)‐3‐hydroxypregnan‐20‐one (allopregnanolone, ALLO); and (ii) the combined effects of naltrexone or genotype with alcohol administration on neurosteroid levels in a sample of at‐risk drinkers.Methods:  Participants were 32 (9 females) nontreatment‐seeking heavy drinkers who completed a placebo‐controlled laboratory study of naltrexone (50 mg/d for 3 days) and provided complete sets of serum samples for ALLO assays before and after alcohol administration under both naltrexone and placebo conditions.Results:  Naltrexone treatment raised ALLO levels among carriers of the Asp40 allele, but not homozygotes for the Asn40 allele. The Asn40Asp polymorphism did not moderate effects of naltrexone on cortisol levels. Ethanol infusion modestly reduced ALLO levels in all subjects, independent of genotype or naltrexone exposure.Conclusions:  Naltrexone increased ALLO levels among individuals with the Asn40Asp allele suggesting a potential neurosteroid contribution to the neuropharmacological effects of naltrexone among Asp40 carriers.

publication date

  • August 1, 2010

has restriction

  • closed

Date in CU Experts

  • June 16, 2014 9:30 AM

Full Author List

  • Ray LA; Hutchison KE; Ashenhurst JR; Morrow AL

author count

  • 4

Other Profiles

International Standard Serial Number (ISSN)

  • 0145-6008

Electronic International Standard Serial Number (EISSN)

  • 1530-0277

Additional Document Info

start page

  • 1479

end page

  • 1487


  • 34


  • 8