title: Dynamic changes of striatal dopamine D2 receptor binding at later stages after unilateral lesions of the medial forebrain bundle in Parkinsonian rat models.
abstract: Our previous study regarding the changes of D(2) receptor in nigrostriatal dopamine system at an early stage (4 weeks after lesion) indicated a different functional activity of striatal D(2) receptor between two different rat parkinsonian models, lesioning with 6-hydroxydopamine in the striatum and in the medial forebrain bundle (MFB). In the present study, we further examined binding of D(2) receptor as well as pre-synaptic dopamine transporter (DAT) at later stages (6 months after lesion) both in the striatal and MFB lesion models. The D(2) receptor binding in MFB model at 6 months after lesion was significantly lower than that at 4 weeks after lesion, albeit it was still higher than the normal side. The D(2) receptor binding in striatal model was decreased to the same extent at both 4 weeks and 6 months after lesion. DAT binding decreased at 6 months after lesion, more profound in MFB model, and the degree of reduction was not different from that at 4 weeks after lesion. These findings indicated different dynamic processes of the D(2) receptor and DAT during a longer time observation in the striatal and MFB lesion models. The dynamic changes of D(2) receptor activity after lesion should be considered when selecting 6-hydroxydopamine-induced rat parkinsonian models.
authors.affiliation: Department of Neurosurgery, Hamamatsu University School of Medicine 1-20-1 Handayama, Higashi-ku, Hamamatsu 431-3192, Japan.
authors.forename: Wei
authors.initials: W
authors.lastname: Sun
authors.forename: Kenji
authors.initials: K
authors.lastname: Sugiyama
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Asakawa
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yamaguchi
authors.forename: Soichi
authors.initials: S
authors.lastname: Akamine
authors.forename: Yasuomi
authors.initials: Y
authors.lastname: Ouchi
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Magata
authors.forename: Hiroki
authors.initials: H
authors.lastname: Namba
mesh_terms: D000818:Animals; D003342:Corpus Striatum / Q000000981:diagnostic imaging / Q000378:metabolism*; D004298:Dopamine / Q000502:physiology; D018492:Dopamine Antagonists / Q000378:metabolism; D050483:Dopamine Plasma Membrane Transport Proteins / Q000378:metabolism; D007150:Immunohistochemistry; D008297:Male; D008474:Medial Forebrain Bundle / Q000000981:diagnostic imaging / Q000293:injuries* / Q000473:pathology; D016627:Oxidopamine; D010302:Parkinson Disease, Secondary / Q000139:chemically induced / Q000378:metabolism* / Q000473:pathology; D049268:Positron-Emission Tomography; D020891:Raclopride / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D017448:Receptors, Dopamine D2 / Q000378:metabolism*; D013565:Sympatholytics; D014446:Tyrosine 3-Monooxygenase / Q000378:metabolism
chemical_list: D018492:Dopamine Antagonists; D050483:Dopamine Plasma Membrane Transport Proteins; D017448:Receptors, Dopamine D2; D013565:Sympatholytics; D020891:Raclopride; D016627:Oxidopamine; D014446:Tyrosine 3-Monooxygenase; D004298:Dopamine