CALB1 and Parkinson disease: There was significanlty higher expression of calbindin (P = 0.0178; Figures 3C,D, 4B), calretinin (P = 0.0366; Figure 4B) and parvalbumin (P = 0.0001; Figures 3A,B, 4B) in the cell bodies and neurites (% of area fraction) of neurons in the AONrb of PD patients compared with controls.