Repeated injections of sulpiride into the medial prefrontal cortex induces sensitization to cocaine in rats
by
Steketee JD, Walsh TJ.
Department of Pharmacology,
University of Tennessee Health Science Center,
874 Union Avenue/Room 115 Crowe,
Memphis, 38163, TN, USA,
[email protected].
Psychopharmacology (Berl). 2004 Dec 24

ABSTRACT

RATIONALE: Recent studies have suggested that the medial prefrontal cortex (mPFC) plays an important role in the development of sensitization to cocaine. In particular, a recent report proposed that sensitization is associated with a decreased dopamine D(2) receptor function in the mPFC. The present study was designed to further examine the involvement of mPFC dopamine D(2) receptors in cocaine sensitization. OBJECTIVES: The experiments described below sought to determine the effects of acute or repeated intra-mPFC injections of the dopamine D(2) antagonist sulpiride on subsequent motor-stimulant and nucleus accumbens dopamine responses to cocaine. METHODS: Rats received bilateral cannulae implants above the ventral mPFC for microinjections and above the nucleus accumbens for in vivo microdialysis. Initial studies examined the effects of intra-mPFC sulpiride pretreatment on the acute motor-stimulant and nucleus accumbens dopamine responses to cocaine. Follow-up studies determined the effects of repeated intra-mPFC sulpiride injections on subsequent behavioral and nucleus accumbens dopamine responses to a cocaine challenge. RESULTS: Intra-mPFC sulpiride enhanced the cocaine-induced increases in motor activity and dopamine overflow in the nucleus accumbens. Repeated intra-mPFC sulpiride induced behavioral and neurochemical cross-sensitization to cocaine. CONCLUSIONS: The data support previous findings that sensitization is associated with a decrease in dopamine D(2) receptor function in the mPFC.

Sulpiride
Sensitisation
The pleasure centres
The nucleus accumbens
Dopamine/D1receptors
Dopamine/D2 receptors
Dopamine/D3 receptors
Dopamine/D4 receptors

01 02 03 04 05 06 07 08 09 10 11 12
13 14 15 16 17 18 19 20 21 22 23 24

Refs
HOME
HedWeb
cannabis-marijuana.com
Future Opioids
BLTC Research
Utopian Surgery?
The Hedonistic Imperative
MDMA: Utopian Pharmacology
When Is It Best to Take Crack Cocaine?

The Good Drug Guide
The Responsible Parent's Guide To
Healthy Mood Boosters For All The Family