Fig 2. Development of a turning bias over time in rats overexpressing p62 unilaterally in the substantia nigra.

Amphetamine-stimulated rotations occur when there is a large side-to-side difference in dopamine levels in the nigrostriatal pathway in rats, i.e., when there is a large loss of dopamine neurons on one side. A) In the p62 group, the behavioral phenotype of ipsilateral turning bias developed by 12 weeks (N = 7, P < 0.05, t-test), but not at earlier times in the p62 group. B) Turning bias did not manifest in a group of rats expressing the control protein GFP (N = 4).