Regional differences in the regulation of acetylcholine release upon D2 dopamine and N-methyl-D-aspartate receptor activation in rat nucleus accumbens and neostriatum.
The effect of D2 dopamine receptor activation on either the electrically, or N-methyl-D-aspartate induced release of radiolabeled acetylcholine (ACh) was investigated in different areas of the nucleus accumbens and the neostriatum of rats, by using a superfusion technique. Sequential slices of 100 microns were chopped along either a rostrocaudal, mediolateral or dorsoventral axis. In every slice the effect of a supramaximal concentration of the selective D2 receptor agonist quinpirole on the release of ACh was measured. In the entire neostriatum the release of ACh was reduced by approximately 70% in the presence of quinpirole. By contrast, in the nucleus accumbens, a gradual decrease in the inhibitory effect of quinpirole on the release of ACh was observed along both the rostral-to-caudal and the lateral-to-medial axes. Whereas in the rostrolateral part a 50% inhibition could be observed, in the caudomedial part no significant inhibition could be detected. Also the N-methyl-D-aspartate induced release of ACh was smaller in the caudomedial part as compared to the rostrolateral part of the nucleus accumbens. It is concluded that the nucleus accumbens is a very heterogeneous structure with respect to the regulation of the release of ACh by D2 dopamine and N-methyl-D-aspartate receptor activation.
Department of Anatomy, Medical Faculty, Free University, Amsterdam, The Netherlands.
J M
JM
Henselmans
J C
JC
Stoof
D000109:Acetylcholine / Q000378:metabolism / Q000502:physiology*; D000818:Animals; D002794:Choline / Q000378:metabolism; D003342:Corpus Striatum / Q000187:drug effects / Q000502:physiology*; D004298:Dopamine / Q000378:metabolism; D015259:Dopamine Agents / Q000494:pharmacology*; D004558:Electric Stimulation; D004873:Ergolines / Q000494:pharmacology*; D066298:In Vitro Techniques; D007700:Kinetics; D008297:Male; D016202:N-Methylaspartate / Q000494:pharmacology*; D009714:Nucleus Accumbens / Q000187:drug effects / Q000502:physiology*; D009928:Organ Specificity; D019257:Quinpirole; D051381:Rats; D011919:Rats, Inbred Strains; D011954:Receptors, Dopamine / Q000187:drug effects / Q000502:physiology*; D017448:Receptors, Dopamine D2; D016194:Receptors, N-Methyl-D-Aspartate / Q000187:drug effects / Q000502:physiology*
D015259:Dopamine Agents; D004873:Ergolines; D011954:Receptors, Dopamine; D017448:Receptors, Dopamine D2; D016194:Receptors, N-Methyl-D-Aspartate; D019257:Quinpirole; D016202:N-Methylaspartate; D002794:Choline; D000109:Acetylcholine; D004298:Dopamine