Effects of intraaccumbens administration of SCH-23390 on cocaine-induced locomotion and conditioned place preference

Synapse. 1998 Oct;30(2):181-93. doi: 10.1002/(SICI)1098-2396(199810)30:2<181::AID-SYN8>3.0.CO;2-8.


The effects of systemic (0-1.0 mg/kg) or intraaccumbens (0-1.0 microg/side) administration of SCH-23390 on cocaine-induced (0 or 4.2 mg/kg, i.v.) locomotion, sniffing, and conditioned place preference (CPP) were investigated in rats. After behavioral testing was completed, animals were injected with their respective dose of SCH-23390 into the nucleus accumbens (NAc), followed by a systemic injection of the irreversible antagonist N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline (EEDQ). Receptors occupied by intraaccumbens SCH-23390, and therefore protected from EEDQ-induced inactivation, were then quantified from autoradiograms of sections labeled with 3H-SCH-23390. Systemic administration of 0.5 and 1.0 mg/kg SCH-23390 reversed cocaine-induced locomotion, sniffing, and CPP, suggesting that stimulation of D1-like receptors is necessary for these behavioral changes. Intraaccumbens administration of 1.0 microg/side SCH-23390 reversed cocaine-CPP, and this dose occupied D1-like receptors primarily in the rostral pole of the NAc. Intraaccumbens administration of 0.5 microg/side SCH-23390 reversed cocaine-induced locomotion. However, this dose occupied a similar number of D1-like receptors in the NAc as a lower and behaviorally ineffective dose of 0.1 microg/side, but occupied more receptors in the caudate-putamen relative to both the 0.1 and 1.0 microg/side doses. These findings suggest that stimulation of D1-like receptors in the NAc is necessary for cocaine-CPP, but not for cocaine-induced locomotion.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Benzazepines / administration & dosage
  • Benzazepines / pharmacology*
  • Cocaine / pharmacology*
  • Conditioning, Operant / drug effects*
  • Dopamine Agonists / administration & dosage
  • Dopamine Agonists / pharmacology*
  • Dopamine Uptake Inhibitors / pharmacology*
  • Injections
  • Male
  • Motor Activity / drug effects*
  • Nucleus Accumbens / physiology*
  • Quinolines / pharmacology
  • Rats
  • Rats, Sprague-Dawley
  • Receptors, Dopamine / drug effects


  • Benzazepines
  • Dopamine Agonists
  • Dopamine Uptake Inhibitors
  • Quinolines
  • Receptors, Dopamine
  • EEDQ
  • Cocaine