Neurobiology of Disease 35 (2009) 348–351 Contents lists available at ScienceDirect Neurobiology of Disease The blood–brain barrier is intact after levodopa-induced dyskinesias in parkinsonian primates—Evidence from in vivo neuroimaging studies Arnar Astradsson a,d, Bruce G. Jenkins a,b, Ji-Kyung Choi b, Penelope J. Hallett a,d, Michele A. Levesque a,d,Jack S. McDowell a,d, Anna-Liisa Brownell a,c, Roger D. Spealman a,d, Ole Isacson a,d,⁎a Harvard University and McLean Hospital, NINDS Udall Parkinson's Disease Research Center of Excellence, Belmont, MA, USAb Massachusetts General Hospital (MGH) Nuclear Magnetic Resonance Center, Athinoula A. Martinos Center for Biomedical Imaging, Boston, MA, USAc MGH Positron Emission Tomography Center, Massachusetts General Hospital, Boston, MA, USAd New England Primate Research Center, Harvard Medical School, Southborough, MA, USA