Impairment of nigrostriatal dopamine neurotransmission by manganese is mediated by pre-synaptic mechanism(s): implications to manganese-induced parkinsonism
| Autor: | Mohab Alexander, Jennifer L. McGlothan, Tore Syversen, Luu Pham, Neal C. Burton, Dean F. Wong, Michael Griswold, Yun Zhou, Jay S. Schneider, Tomás R. Guilarte, Tatyana Verina |
|---|---|
| Rok vydání: | 2008 |
| Předmět: |
Male
medicine.medical_specialty Tyrosine 3-Monooxygenase Dopamine Dopamine Agents Tetrabenazine Substantia nigra Striatum Neurotransmission Synaptic Transmission Biochemistry Article Synapse Cellular and Molecular Neuroscience chemistry.chemical_compound Cocaine Parkinsonian Disorders Internal medicine Basal ganglia Image Processing Computer-Assisted medicine Animals Amphetamine Neurotransmitter Dopamine Plasma Membrane Transport Proteins Manganese Dose-Response Relationship Drug Cyclohexanols Corpus Striatum Substantia Nigra Disease Models Animal Macaca fascicularis Endocrinology chemistry Positron-Emission Tomography medicine.drug |
| Zdroj: | Journal of Neurochemistry. 107:1236-1247 |
| ISSN: | 1471-4159 0022-3042 |
| Popis: | The long-term consequences of chronic manganese (Mn) exposure on neurological health is a topic of great concern to occupationally-exposed workers and in populations exposed to moderate levels of Mn. We have performed a comprehensive assessment of Mn effects on dopamine (DA) synapse markers using positron emission tomography (PET) in the non-human primate brain. Young male Cynomolgus macaques were given weekly i.v. injections of 3.3-5.0 mg Mn/kg (n = 4), 5.0-6.7 mg Mn/kg (n = 5), or 8.3-10.0 mg Mn/kg (n = 3) for 7-59 weeks and received PET studies of various DA synapse markers before (baseline) and at one or two time points during the course of Mn exposure. We report that amphetamine-induced DA release measured by PET is markedly impaired in the striatum of Mn-exposed animals. The effect of Mn on DA release was present in the absence of changes in markers of dopamine terminal integrity determined in post-mortem brain tissue from the same animals. These findings provide compelling evidence that the effects of Mn on DA synapses in the striatum are mediated by inhibition of DA neurotransmission and are responsible for the motor deficits documented in these animals. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Plný text