Carbachol and naloxone synergistically elevate dopamine release in rat striatum: an in vivo microdialysis study.
Striatal dopamine (DA) release increased to 184% of baseline after 10-20 min of continuous intrastriatal perfusion with 10 mM carbachol, dropping to 124% after 30-40 min. The addition of 100 microM naloxone amplified (to 236% of baseline) and prolonged the increase in DA release, but naloxone alone (up to 1 mM) had no effect. These data suggest that activation of opiate-releasing striatal neurons suppresses cholinergic stimulation of DA release.
Kischka
U
U
Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge 02139.
Farber
S A
SA
Marshall
D
D
Wurtman
R J
RJ
D000818:Animals; D002217:Carbachol / Q000494:pharmacology*; D003342:Corpus Striatum / Q000187:drug effects / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D004357:Drug Synergism; D007700:Kinetics; D008297:Male; D017551:Microdialysis / Q000379:methods; D009270:Naloxone / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors
D009270:Naloxone; D002217:Carbachol