Apomorphine-induced changes in striatal and pallidal neuronal activity are modified by NMDA and muscarinic receptor blockade.
Systemic administration of apomorphine decreased the firing rate of caudate Type I neurons and increased the firing rate, presumably via disinhibition (16), of globus pallidus (GP) Type II neurons. In the present study, extracellular single-unit recording techniques were used to demonstrate that systemic administration of the NMDA antagonist dizocilpine (MK801) reduced both the inhibition of caudate neurons by apomorphine as well as the apomorphine-induced excitation of GP neurons. In addition, the muscarinic antagonists atropine and scopolamine had effects similar to dizocilpine. Thus, both glutamate and acetylcholine appear to play a role in dopaminergic modulation of striatal and GP activity.
Kelland
M D
MD
Experimental Therapeutics Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892.
Walters
J R
JR
D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D001058:Apomorphine / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D001285:Atropine / Q000494:pharmacology; D002421:Caudate Nucleus / Q000187:drug effects* / Q000502:physiology; D016291:Dizocilpine Maleate / Q000008:administration & dosage; D004594:Electrophysiology; D005917:Globus Pallidus / Q000187:drug effects* / Q000502:physiology; D008297:Male; D018727:Muscarinic Antagonists; D051381:Rats; D011919:Rats, Inbred Strains; D016194:Receptors, N-Methyl-D-Aspartate / Q000037:antagonists & inhibitors*; D012601:Scopolamine / Q000494:pharmacology
D018727:Muscarinic Antagonists; D016194:Receptors, N-Methyl-D-Aspartate; D016291:Dizocilpine Maleate; D001285:Atropine; D012601:Scopolamine; D001058:Apomorphine; D000109:Acetylcholine