Subcutaneous rotenone exposure causes highly selective dopaminergic degeneration and α-synuclein aggregation

TB Sherer, JH Kim, R Betarbet, JT Greenamyre - Experimental neurology, 2003 - Elsevier
TB Sherer, JH Kim, R Betarbet, JT Greenamyre
Experimental neurology, 2003Elsevier
Previous studies demonstrated that chronic systemic exposure to the pesticide and
mitochondrial toxin rotenone through jugular vein cannulation reproduced many features of
Parkinson's disease (PD) in rats, including nigrostriatal dopaminergic degeneration and
formation of α-synuclein-positive cytoplasmic inclusions in nigral neurons (R. Betarbet et al.,
2000, Nat. Neurosci. 3, 1301–1306). Although novel and conceptually important, the
rotenone model of PD suffered from being extremely labor-intensive. The current paper …
Previous studies demonstrated that chronic systemic exposure to the pesticide and mitochondrial toxin rotenone through jugular vein cannulation reproduced many features of Parkinson's disease (PD) in rats, including nigrostriatal dopaminergic degeneration and formation of α-synuclein-positive cytoplasmic inclusions in nigral neurons (R. Betarbet et al., 2000, Nat. Neurosci. 3, 1301–1306). Although novel and conceptually important, the rotenone model of PD suffered from being extremely labor-intensive. The current paper demonstrates that these same features of PD can be reproduced by chronic, systemic exposure to rotenone following implantation of subcutaneous osmotic pumps. Chronic subcutaneous exposure to low doses of rotenone (2.0–3.0 mg/kg/day) caused highly selective nigrostriatal dopaminergic lesions. Striatal neurons containing DARPP-32 (dopamine and cAMP-regulated phosphoprotein) remained intact with normal morphology, and NeuN staining revealed normal neuronal nuclear morphology. Neurons of the globus pallidus and subthalamic nucleus were spared. Subcutaneous rotenone exposure caused α-synuclein-positive cytoplasmic aggregates in nigral neurons. This new protocol for chronic rotenone administration is a substantial improvement in terms of simplicity and throughput.
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