Table 1.

Known Functions of the Endocannabinoid System Along the Upper Alimentary Tract

Function	Brief summary	Related studies
Appetite regulation	1. Stimulates appetite, especially high energy, fatty foods	Argueta and DiPatrizio18
	2. Induces hyperphagia, potential target for obesity therapy, generates hunger signal	DiPatrizio et al.17
		DiPatrizio et al.16
Nociception/emesis	1. Stimulation of CB1 receptor in CNS leads to nausea, therapeutic target for antiemetic effect of exogenous cannabinoid therapy	Van Sickle et al.19
		Rock and Parker71
Motility	1. Multiple receptors (CB1 and CB2) thought to influence contractile and relaxant forces in stomach	Hornby and Prouty10
	2. Modulates intestinal propulsion, GPR55 inhibits whole gut transit time, modulation of cholinergical and vagal stimulation of upper GI tract	Yuece et al.12
		Storr et al.21
	3. Enhances gut motility in setting of inflammation	Izzo et al.24
		Yang et al.26
		Li et al.27
Gastric acid and intestinal secretions	1. Exhibits antisecretory effects on gastric acid	Adami et al.15
	2. Implicated in mitigating inflammation and mucosal damage in GERD	Calabrese et al.25
	3. Effect on transient lower esophageal relaxation	Lehmann et al.33
Inflammation and immunity	1. Anti-inflammatory effects in esophageal reflux disease	Calabrese et al.25
	2. CB2 receptor downregulates inflammation and associated hypermotility in disease state	Izzo23
Analgesia	1. Increases pain threshold	Clapper et al.65
		Malik et al.66

CNS, central nervous system; GERD, gastroesophageal reflux disease; GI, gastrointestinal; GPR55, G-protein receptor 55.