Table 1.
Major regulators of epithelial-neuronal communication in the small intestine and colon.
| Transmitter | Epithelial Cell Source | Model System | Techniques Used to Identify Source of Transmitter | Ref |
|---|---|---|---|---|
| Acetylcholine (ACh) | Tuft cells | Mouse: small intestine and colon tissue | Immunohistochemistry (IHC), in situ hybridization, transgenic fluorescent reporter | [82] |
| Adenosine triphosphate (ATP) | All | Rat: colon tissue | Luciferin-luciferase ATP release assay | [48] |
| All | Human: CCD 841 cell line | Luciferin-luciferase ATP release assay | [51] | |
| All | Mouse: colon epithelium primary culture | Luciferin-luciferase ATP release assay | [52] | |
| L-cells | GLUTag cell line Mouse: cultures of small intestine epithelium Human: culture of colon epithelium |
Epithelial-neuronal co-cultures, luciferin-luciferase ATP release assay, sniffer patch IHC |
[56] | |
| All | CCD 841 cell line Mouse: colon tissue |
qRT-PCR, IHC, luciferin-luciferase assay qRT-PCR, IHC |
[51] | |
| Glutamate (Glu) | L-cells | Rat: small intestine tissue | IHC | [77] |
| L-cells | GLUTag cell line | In vitro chemically evoked release | [18] | |
| I-cells | Mouse: small intestine tissue | IHC, in vitro optogenetics | [47] | |
| Cyclic guanosine-3’,5’-monophosphate (cGMP) | All | Human: T84 cell line | Enzyme immunoassay | [102] |
| Serotonin (5-HT) | EC cells | Rat: small intestine tissue | Immunoelectron microscopy | [64] |
| EC cells | Mouse: small intestine, cultured organoids, ex vivo colon-nerve preparation | IHC, in vitro electrophysiology, 5-HT biosensors (sniffer patch) | [22] | |
| EC cells | Mouse: small intestine and colon, cultured organoids | IHC, in vitro calcium imaging, 5-HT biosensors (sniffer patch) | [69] | |
| Trypsin-3 | All | Rat: colon tissue Human: colon tissue, Caco-2 cell line |
IHC, Western blot | [96] |