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Decrease in [3H]hemicholinium binding to high-affinity choline uptake sites in deafferented striatum: restoration by oxiracetam.

G Forloni·N Angeretti·D Amoroso·A Addis·S Consolo
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Abstract

Frontal cortical deafferentation of the rat striatum reduces the tone of striatal cholinergic neurons. We used biochemical and autoradiographic techniques to investigate whether the [3H]hemicholinium-3 ([3H]HCh-3) binding to sodium-dependent high-affinity choline uptake sites was influenced by this lesion. Frontal deafferentation produced a reduction of about 30% in the number of [3H]HCh-3 binding sites (Bmax) in striatum, with no significant changes in the binding affinity (Kd). Autoradiography showed a significant reduction of [3H]HCh-3 binding sites in the anteromedial portion of the striatum, but not in the posterior part of frontal deafferented rats. Oxiracetam (100 mg/kg), a nootropic drug, did not affect the distribution of [3H]HCh-3 binding sites in sham-operated rats but completely overcame the reduction in the number of [3H]HCh-3 binding sites in deafferented striatum.

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Afferent PathwaysAnimalsAutoradiographyCholineCorpus StriatumDenervationFemaleHemicholinium 3PyrrolidinesRatsRats, Inbred StrainsTritiumJournal ArticleResearch Support, U.S. Gov't, Non-P.H.S.

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G Forloni, N Angeretti, D Amoroso, A Addis, S Consolo. 1990-10-15. Decrease in [3H]hemicholinium binding to high-affinity choline uptake sites in deafferented striatum: restoration by oxiracetam.. https://doi.org/10.1016/0006-8993(90)90674-z

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