Table 1.

ENS degeneration in different GI tracts.

Authors (Year)	GI Tract	Species	Parkinson’s Disease Model
Braak et al., 2003 [9]	Distal esophagus, stomach	Human	-
Natale et al., 2010 [11]	Duodenum	Mouse	MPTP
Clairembault et al., 2015 [55]	Descending colon, sigmoid	Human	-
Chung et al., 2021 [58]	Stomach, small intestine	Human	-
Lebouvier et al., 2008 [62]	Colon	Human	-
Ohlsson et al., 2019 [63]	Colon	Human	-
Fenyi et al., 2021 [64]	Stomach	Human	-
Killinger et al., 2019 [65]	Appendix	Human	-
Annerino et al., 2012 [67]	Stomach, duodenum, ileum, colon	Human	-
Anderson et al., 2007 [71]	Colon	Mouse	MPTP
Drolet et al., 2009 [72]	Small intestine	Rat	Rotenone
Miyazaki et al., 2020 [75]	Intestine	Mouse	Rotenone
Fornai et al., 2016 [76]	Colon	Rat	6-OHDA