Effects of ceftriaxone on chronic ethanol consumption: a potential role for xCT and GLT1 modulation of glutamate levels in male P rats

J Mol Neurosci. 2014 Sep;54(1):71-7. doi: 10.1007/s12031-014-0251-5. Epub 2014 Feb 18.

Abstract

Alterations in glutamatergic neurotransmission have been suggested to affect many aspects of neuroplasticity associated with alcohol/drug addiction. We have previously shown that ceftriaxone, a β-lactam antibiotic known to upregulate glutamate transporter 1 (GLT1), reduced ethanol intake after 5 weeks of free choice ethanol drinking paradigm in male alcohol-preferring (P) rats. Evidence suggests that differential effects involving alterations of glutamatergic neurotransmission occur after long-term ethanol consumption. In this study, we tested whether the efficacy of administration of ceftriaxone persists after 14 weeks of free access to 15 and 30 % ethanol in male P rats. After 14 weeks of ethanol consumption, male P rats were administered ceftriaxone (100 mg/kg, intraperitoneal (i.p.)) or saline vehicle for 5 days. We found that ceftriaxone treatment resulted in a significant reduction in ethanol intake starting from day 2 (48 h after the first i.p. injections of ceftriaxone) through day 14, 10 days after final injection. Western blot analysis of brain samples from animals euthanized 24 h after treatment with the last dose of ceftriaxone revealed a significant upregulation of cystine/glutamate exchanger (xCT) and GLT1 levels in prefrontal cortex, nucleus accumbens, and amygdala as compared to saline vehicle-treated group. These findings demonstrated the effectiveness of ceftriaxone in attenuating ethanol intake in a chronic consumption paradigm. These might be due in part through the upregulation of both xCT and GLT1 levels in brain reward regions. Thus, the drug has a potential therapeutic action for the treatment of alcohol dependence.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Alcoholism / drug therapy
  • Alcoholism / metabolism*
  • Amino Acid Transport Systems, Acidic / genetics
  • Amino Acid Transport Systems, Acidic / metabolism*
  • Animals
  • Brain / drug effects
  • Brain / metabolism
  • Ceftriaxone / pharmacology*
  • Ceftriaxone / therapeutic use
  • Excitatory Amino Acid Transporter 2 / genetics
  • Excitatory Amino Acid Transporter 2 / metabolism*
  • Glutamic Acid / metabolism*
  • Male
  • Rats
  • Up-Regulation

Substances

  • Amino Acid Transport Systems, Acidic
  • Excitatory Amino Acid Transporter 2
  • Slc1a2 protein, rat
  • xCT protein, rat
  • Glutamic Acid
  • Ceftriaxone