کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4335247 1295140 2011 10 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Altered striatal dopamine release following a sub-acute exposure to manganese
موضوعات مرتبط
علوم زیستی و بیوفناوری علم عصب شناسی علوم اعصاب (عمومی)
پیش نمایش صفحه اول مقاله
Altered striatal dopamine release following a sub-acute exposure to manganese
چکیده انگلیسی

Certain metals that are necessary for regulating biological function at trace levels hold the potential to become neurotoxic when in excess. Specifically, chronic exposure to high levels of manganese leads to manganism, a neurological disorder that exhibits both motor and learning deficits similar to Parkinson's disease. Since Parkinson's disease symptomatology is primarily attributed to dopamine neurodegeneration in the striatum, dopamine system dysfunction has been implicated in the onset of manganism. In this study, dopamine system function in the dorsal striatum was evaluated in C57Bl/6 mice, 1, 7, and 21 days following repeated injections of manganese(II) chloride (50 mg/kg, subcutaneous) intermittently for 7 days. Tissue content analysis confirmed the presence of persistent accumulation of manganese in the striatum up to 21 days after cessation of treatment. In vitro fast scan cyclic voltammetry examined the effect of sub-acute manganese on electrically stimulated dopamine release and uptake in the striatum. While no difference was observed in uptake rates following manganese treatment, dopamine release was attenuated on days 7 and 21, compared to control levels. Basal levels of extracellular dopamine determined by the zero net flux microdialysis method were significantly lower in manganese-treated mice at 7 days post-treatment. On the other hand, potassium stimulated increases in extracellular dopamine were attenuated at all three time points. Together, these findings indicate that repeated manganese exposure has long-term effects on the regulation of exocytotic dopamine release in the striatum, which may be involved in the mechanism underlying manganese toxicity.


► Tissue content, microdialysis, and FSCV used to study sub-acute Mn treated mice.
► Sub-acute Mn treatment to mice over 7 days; neurochemical analysis over 21 days.
► Tissue content confirmed the accumulation of striatal Mn 21 days past final treatment.
► Microdialysis elucidated attenuation in basal and potassium stimulated DA levels.
► FSCV shows lowered release with no difference in DA transporter or D2 receptors.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Neuroscience Methods - Volume 202, Issue 2, 15 November 2011, Pages 182–191
نویسندگان
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