Figure 1 Distribution of TH-immunoreactive neurons in the ventral periaqueductal gray

Upper panel: Fifty-micrometer section of the human midbrain showing the distribution of tyrosine hydroxylase (TH) immunoreactive neurons in the ventral periaqueductal gray (PAG). Lower panel: TH-immunoreactive cells in the ventral PAG in a control (75-year-old man, 18-h postmortem delay), a 70-year-old man with multiple system atrophy (MSA) (postmortem delay 20 h), and an 80-year-old man with neocortical stage Lewy body disease (LBD) (postmortem delay, 15 h). Aq = aqueduct; bar = 500 μm upper panel; bar = 50 μm lower panels.