title: NMDA receptors in the rostral and intermediate-caudal striatum play an opposite role in regulation of the muscle tone in rats.
abstract: The aim of the study was to assess the contribution of the NMDA receptors in the caudate-putamen to the regulation of the muscle tone. The experiment was carried out on male Wistar rats. The hind foot of a rat was flexed or extended at the ankle joint by 25 degrees and the resistance of the foot to passive movements was measured. Haloperidol (1 mg/kg ip) induced the muscle rigidity. The competitive antagonist of NMDA receptors, (+/-)-2-amino-5-phosphonopentanoic acid (AP-5), injected in doses of 2 and 5 micrograms/0.5 microliter bilaterally into rostral regions of the caudate-putamen, inhibited the muscle rigidity induced by haloperidol. In contrast, AP-5 injected bilaterally in the same doses into the intermediate-caudal region of the caudate-putamen in rats not pretreated with haloperidol, induced muscle rigidity. The present results seem to suggest that NMDA receptors localized in the rostral and intermediate-caudal regions of the caudate-putamen play an opposite role in regulation of the muscle tone in rats.
authors.affiliation: Department of Neuro-Psychopharmacology, Polish Academy of Sciences, Kraków, Poland.
authors.forename: K
authors.initials: K
authors.lastname: Ossowska
authors.forename: J
authors.initials: J
authors.lastname: Konieczny
mesh_terms: D015763:2-Amino-5-phosphonovalerate / Q000494:pharmacology; D000818:Animals; D002421:Caudate Nucleus / Q000502:physiology*; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D006220:Haloperidol / Q000494:pharmacology; D008297:Male; D009127:Muscle Rigidity / Q000503:physiopathology; D009129:Muscle Tonus / Q000187:drug effects / Q000502:physiology*; D011699:Putamen / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D016194:Receptors, N-Methyl-D-Aspartate / Q000187:drug effects / Q000502:physiology*
chemical_list: D018691:Excitatory Amino Acid Antagonists; D016194:Receptors, N-Methyl-D-Aspartate; D015763:2-Amino-5-phosphonovalerate; D006220:Haloperidol