In detail, in a murine PD model of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced dopaminergic degeneration, the authors observed an increased level of P-gp substrate bromocriptine in the brain, suggesting either disruption of BBB or alteration of active efflux of the drug. The gene discussed is PGP; the disease is Parkinson disease.