Distribution of zinc in the substantia nigra of rats treated with 6-hydroxydopamine.
To study the relationship between tissue accumulation of Zinc (Zn) and neurodegeneration in the nigrostriatal dopaminergic pathway, 65Zn distribution in this pathway was examined after unilateral injection of 6-hydroxydopamine (6-OHDA) into the substantia nigra of rats. When 65ZnCl2 was intravenously injected 4 days after treatment with 6-OHDA, 65Zn was concentrated in the ipsilateral substantia nigra 6 days after 65Zn injection. On the other hand, 19 d after treatment with 6-OHDA, 65Zn distribution in the ipsilateral substantia nigra was decreased to the level of the contralateral one. When NH4(99)TcO4, which cannot go through the blood-brain barrier, was injected into rats 4 d after treatment with 6-OHDA, 99Tc was concentrated in the ipsilateral substantia nigra 30 min after 99Tc injection, but no longer detectable 6 d after injection. These results suggest that Zn is necessary for a repair process called replacement gliosis after the death of neurons and that excess Zn does not accumulate in the lesion after completion of the gliosis.
Takeda
A
A
Department of Radiobiochemistry, School of Pharmaceutical Sciences, University of Shizuoka, Japan.
Sawashita
J
J
Takefuta
S
S
Okada
S
S
D015102:3,4-Dihydroxyphenylacetic Acid / Q000032:analysis; D018663:Adrenergic Agents; D000818:Animals; D001345:Autoradiography; D001812:Blood-Brain Barrier / Q000187:drug effects; D002712:Chlorides / Q000008:administration & dosage / Q000493:pharmacokinetics*; D003342:Corpus Striatum / Q000000981:diagnostic imaging / Q000378:metabolism; D005911:Gliosis / Q000473:pathology; D006719:Homovanillic Acid / Q000032:analysis; D066298:In Vitro Techniques; D007275:Injections, Intravenous; D008297:Male; D009410:Nerve Degeneration / Q000139:chemically induced / Q000378:metabolism; D016627:Oxidopamine; D000644:Quaternary Ammonium Compounds; D011877:Radionuclide Imaging; D051381:Rats; D017208:Rats, Wistar; D013378:Substantia Nigra / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000473:pathology; D017556:Technetium Compounds; D013997:Time Factors; D015032:Zinc / Q000378:metabolism* / Q000493:pharmacokinetics; D017967:Zinc Compounds / Q000008:administration & dosage / Q000493:pharmacokinetics*; D015037:Zinc Radioisotopes
D018663:Adrenergic Agents; D002712:Chlorides; D000644:Quaternary Ammonium Compounds; D017556:Technetium Compounds; D017967:Zinc Compounds; D015037:Zinc Radioisotopes; D015102:3,4-Dihydroxyphenylacetic Acid; C111590:ammonium pertechnetate; C016837:zinc chloride; D016627:Oxidopamine; D015032:Zinc; D006719:Homovanillic Acid