Influence of dopaminergic and serotonergic neurons on intravenous ethanol self-administration in the rat

Pharmacol Biochem Behav. 1992 May;42(1):187-92. doi: 10.1016/0091-3057(92)90465-r.


Rats implanted with chronic indwelling intravenous catheters and allowed access to a self-administration apparatus learned to self-inject intravenous ethanol. Ethanol concentrations of 0.5, 1.0, and 2.0%, corresponding to a dose/injection of 1, 2, and 4 mg/kg, respectively, were consistently self-injected. Self-injection was not acquired or maintained with ethanol doses of 0.5 or 8 mg/kg/injection. Saline replacement of ethanol reservoirs led to marked increases in lever-pressing response in animals self-injecting 1, 2, and 4 mg/kg ethanol/injection but not with 0.5 or 8 mg/kg/injection. Neurotoxin-induced lesions of dopamine-(DA) containing neurons in nucleus accumbens septi failed to alter the acquisition or maintenance of ethanol self-injection. Pretreatment with haloperidol (0.05 and 0.1 mg/kg, SC) failed to alter hourly or daily self-injection rates. On the other hand, p-chlorophenylalanine pretreatment increased, while fluoxetine (2.5 and 5.0 mg/kg) administration significantly reduced, self-injected intravenous ethanol. These data suggest that ethanol is self-injected by the rat in a narrow dose range and that 5-hydroxytryptamine (5-HT), but not DA-containing neurons, subserves some function in the reinforcing or aversive affects of ethanol.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Dopamine / physiology*
  • Ethanol / administration & dosage
  • Ethanol / pharmacology*
  • Fenclonine / pharmacology
  • Haloperidol / pharmacology
  • Male
  • Neurons / drug effects
  • Neurons / physiology*
  • Oxidopamine / pharmacology
  • Rats
  • Rats, Inbred Strains
  • Self Administration
  • Serotonin / physiology*


  • Serotonin
  • Ethanol
  • Oxidopamine
  • Haloperidol
  • Fenclonine
  • Dopamine