Fig.1.

(a-f) Lewy pathology in the olfactory bulb and gastric Auerbach plexus visualized in α-synuclein immunohistochemistry (100 μm polyethylene glycol sections). a. Olfactory bulb and anterior olfactory nucleus (aon) (50-year-old male, stage 2). The dorsal motor nucleus of the vagal nerve and intermediate reticular zone in the medulla also contained Lewy neurites and Lewy bodies. Presumably, this non-demented individual would have gone on to develop PD had he lived longer. b. Olfactory bulb and aon (63-year-old female, stage 2). Much less severe pathology was also present in the dorsal motor nucleus of the vagal nerve, intermediate reticular zone, nucleus raphes magnus, and locus coeruleus. c. Tangential section from the gastric cardia showing Lewy neurites (arrowheads, same case as in b). Again, it is presumed that, had she lived longer, this cognitively intact individual would have been diagnosed with PD. d. Intramural Lewy pathology in a section cut tangentially to the surface of the gastric cardia. Also visible (in background) is a large, branching blood vessel lined by thread-like immunoreactive sympathetic nerve fibers. In addition to the occurrence of Lewy neurites and Lewy bodies in the dorsal motor nucleus of the vagal nerve, intermediate reticular zone, nucleus raphes magnus, locus coeruleus, and substantia nigra, some nigral cell loss was also evident in the pars compacta (65-year-old male, stage 3). e. Detail of Lewy neurites in PD penetrating the muscularis mucosa and reaching upwards into the lamina propria (mucosa) where they extend between the gastric glands (g) in a perpendicularly cut section (69-year-old female, stage 4). f. Tangential section from the gastric cardia of a PD patient with disease duration of 11 years (78-year-old female, stage 5). Scale bars: a is valid for b; c also applies to d. Stages in parentheses refer to neuropathological stages 1–6 of sporadic PD. Micrographs e, f reproduced with permission from [70].