The overall rod performance test in the MPTP-treated-mouse model of Parkinsonism.
We investigated the usefulness of the Overall Rotarod Performance (ORP) test for evaluating overall locomotory ability in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-injected-mouse model of Parkinson's disease (PD). For this procedure, the mice are pretrained on the rotarod and then tested at a series of increasing speeds, recording the time that the animal remains on the rod at each speed; the overall rod performance (ORP) of each animal is then calculated as the area under the curve in a plot of time-on-the-rod against rotation speed. At 15-day intervals, C57BL/6 mice were injected (or sham-injected) with MPTP, with ORP testing 7-10 days after each injection. After the fourth injection (day 45), mice in the treated group showed clearly lower ORP than mice in the control group (70-90% reduction in ORP), and were thus considered effectively lesioned. Subsequently, we investigated the short-term effects of apomorphine and L-DOPA on ORP in MPTP-treated mice. Apomorphine (at 0.5 or 2.5 mg/kg) had no significant effect, while L-DOPA (at 80 but not at 40 mg/kg) caused almost complete short-term recovery of pretreatment ORP. By about 100 days after the last MPTP injection, MPTP-treated mice showed partial long-term recovery of ORP; at this stage the mice were killed for tyrosine hydroxylase (TH) immunohistochemistry studies. TH immunoreactivity in the striatum showed a strong positive correlation with ORP as tested on day 100. We conclude that the ORP test is useful for evaluating motor deficit in MPTP-treated mice, and the effects of subsequent treatments.
Rozas
G
G
Department of Morphological Sciences, Faculty of Medicine, University of Santiago de Compostela, Spain.
López-Martín
E
E
Guerra
M J
MJ
Labandeira-García
J L
JL
D015632:1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine; D000818:Animals; D001058:Apomorphine / Q000494:pharmacology; D001522:Behavior, Animal / Q000187:drug effects / Q000502:physiology; D003342:Corpus Striatum / Q000503:physiopathology; D004195:Disease Models, Animal; D015259:Dopamine Agents; D018491:Dopamine Agonists / Q000494:pharmacology; D007980:Levodopa / Q000494:pharmacology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009043:Motor Activity / Q000187:drug effects / Q000502:physiology*; D009474:Neurons / Q000201:enzymology; D010302:Parkinson Disease, Secondary / Q000139:chemically induced / Q000503:physiopathology*; D014446:Tyrosine 3-Monooxygenase / Q000032:analysis
D015259:Dopamine Agents; D018491:Dopamine Agonists; D007980:Levodopa; D015632:1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine; D014446:Tyrosine 3-Monooxygenase; D001058:Apomorphine