Motor depressant effects mediated by dopamine D2 and adenosine A2A receptors in the nucleus accumbens and the caudate-putamen.
We compared hypolocomotion and catalepsy mediated by striatal dopamine D2 and adenosine A2A receptors using microinfusions of the adenosine A2A receptor agonist 2-p-(2-carboxyethyl) phenethylamino-5'-N-ethylcarboxamidoadenosine hydrochloride (CGS21680) and the dopamine D2 receptor antagonist raclopride into the nucleus accumbens and the caudate-putamen. The effective doses (ED25/50) of CGS21680 and raclopride which produced equivalent reductions of spontaneous locomotion after microinfusion into the nucleus accumbens were found to induce similar degrees of catalepsy after microinfusion into the caudate-putamen. This comparable, little separation of the effective doses of a dopamine D2 receptor antagonist and an adenosine A2A receptor agonist to produce locomotor inhibition and catalepsy support the idea that adenosine A2A receptor agonists as potential antipsychotic agents may have a similar therapeutic profile as dopamine D2 receptor antagonists.
Hauber
W
W
Department of Animal Physiology, University of Stuttgart, Germany. Hauber@po.uni-stuttgart.de
Münkle
M
M
D000241:Adenosine / Q000031:analogs & derivatives* / Q000494:pharmacology; D000818:Animals; D002375:Catalepsy / Q000503:physiopathology; D002421:Caudate Nucleus / Q000187:drug effects / Q000502:physiology; D065127:Dopamine D2 Receptor Antagonists; D008297:Male; D008845:Microinjections; D009043:Motor Activity / Q000187:drug effects* / Q000502:physiology; D017072:Neostriatum / Q000187:drug effects* / Q000502:physiology; D009714:Nucleus Accumbens / Q000187:drug effects / Q000502:physiology; D010627:Phenethylamines / Q000494:pharmacology*; D058906:Purinergic P1 Receptor Agonists; D011699:Putamen / Q000187:drug effects / Q000502:physiology; D020891:Raclopride; D051381:Rats; D017207:Rats, Sprague-Dawley; D043705:Receptor, Adenosine A2A; D012457:Salicylamides / Q000494:pharmacology*
D065127:Dopamine D2 Receptor Antagonists; D010627:Phenethylamines; D058906:Purinergic P1 Receptor Agonists; D043705:Receptor, Adenosine A2A; D012457:Salicylamides; C061282:2-(4-(2-carboxyethyl)phenethylamino)-5'-N-ethylcarboxamidoadenosine; D020891:Raclopride; D000241:Adenosine