Nicotine and cocaine self-administration using a multiple schedule of intravenous drug and sucrose reinforcement in rats

Behav Pharmacol. 2010 May;21(3):182-93. doi: 10.1097/FBP.0b013e32833a5c9e.

Abstract

There appears to be a relatively narrow range of contingencies in which intravenous (i.v) infusions of nicotine will maintain responding in rats. The schedule of reinforcement typically used when investigating i.v. nicotine self-administration is a simple fixed-ratio (FR) schedule. This study determined if responding in rats could be established using a multiple schedule of either i.v. cocaine or nicotine and sucrose reinforcement. Following training of individual components with each reinforcer, rats were placed on an FR15 60-s timeout multiple schedule of cocaine (0.3 mg/kg/infusion) and sucrose (45 mg pellets) reinforcement or an FR5 60-s timeout multiple schedule of nicotine (0.03 mg/kg/infusion) and sucrose (45 mg pellets) reinforcement. Both cocaine and nicotine maintained significant levels of responding under the multiple schedule. Pretreatment with the dopamine D1 antagonist SCH 23390 increased cocaine-maintained responding, but not sucrose responding. Acute pretreatment with the nicotinic antagonist mecamylamine or SCH 23390 specifically decreased nicotine self-administration. Extinction of the individual nicotine and sucrose components resulted in decreases in responding in each component under extinction. These results indicate that i.v. nicotine maintains responding under a multiple schedule. This procedure may be useful when studying the specificity of drug pretreatments on nicotine self-administration.

Publication types

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

MeSH terms

  • Anesthetics, Local / administration & dosage*
  • Animals
  • Behavior, Animal / drug effects
  • Benzazepines / pharmacology
  • Cocaine / administration & dosage*
  • Conditioning, Operant / drug effects
  • Dopamine Antagonists / pharmacology
  • Dose-Response Relationship, Drug
  • Drug Administration Schedule
  • Extinction, Psychological / drug effects
  • Food Preferences / drug effects*
  • Infusions, Intravenous / methods
  • Male
  • Mecamylamine / pharmacology
  • Nicotine / administration & dosage*
  • Nicotinic Agonists / administration & dosage*
  • Nicotinic Antagonists / pharmacology
  • Rats
  • Rats, Sprague-Dawley
  • Reinforcement, Psychology*
  • Self Administration / methods
  • Sucrose / administration & dosage*

Substances

  • Anesthetics, Local
  • Benzazepines
  • Dopamine Antagonists
  • Nicotinic Agonists
  • Nicotinic Antagonists
  • SCH 23390
  • Sucrose
  • Mecamylamine
  • Nicotine
  • Cocaine