PVALB and Parkinson disease: Immunofluorescent analyses revealed significantly higher expression of parvalbumin in the neuronal cell bodies (cell/mm2) in all of the AON divisions of PD cases compared with controls: the AONrb (P = 0.001; Figures 3A,B, 4A), AONca (P = 0.001; Figure 4A) and the AONpc (P = 0.087; Figure 4A).