biostudies-literatureWei LFlinders FoundationNIDDK NIH HHSNational Institute of Diabetes and Digestive and Kidney DiseasesNIAID NIH HHSNational Institutes of HealthEuropean CommissionNIGMS NIH HHSAustralian Research Council2451-2466.e19https://www.ebi.ac.uk/biostudies/studies/S-EPMC8532026biostudies-literatureUnknown160(7)<h4>Background & aims</h4>Gastrointestinal (GI) motility is regulated by serotonin (5-hydroxytryptamine [5-HT]), which is primarily produced by enterochromaffin (EC) cells in the GI tract. However, the precise roles of EC cell-derived 5-HT in regulating gastric motility remain a major point of conjecture. Using a novel transgenic mouse line, we investigated the distribution of EC cells and the pathophysiologic roles of 5-HT deficiency in gastric motility in mice and humans.<h4>Methods</h4>We developed an inducible, EC cell-specific Tph1^CreERT2/+ mouse, which was used to generate a reporter mouse line, Tph1-tdTom, and an EC cell-depleted line, Tph1-DTA. We examined EC cell distribution, morphology, and subpopulations in reporter mice. GI motility was measured in vivo and ex vivo GastroenterologySerotonin Deficiency Is Associated With Delayed Gastric Emptying.PMC8532026P01 DK041315P30 GM110767R01 DK103055R01 DK094886DP190103525DK094886P01 DK41315R25 AI147369DK103055Keating DJSanders KMSpencer NJHabtezion AMartin AMGottfried-Blackmore AJorgensen BGNguyen LChervo TJin BRo SHa SESingh RJones LAZogg HWei LfalseSerotonin Deficiency Is Associated With Delayed Gastric Emptying.<h4>Background & aims</h4>Gastrointestinal (GI) motility is regulated by serotonin (5-hydroxytryptamine [5-HT]), which is primarily produced by enterochromaffin (EC) cells in the GI tract. However, the precise roles of EC cell-derived 5-HT in regulating gastric motility remain a major point of conjecture. Using a novel transgenic mouse line, we investigated the distribution of EC cells and the pathophysiologic roles of 5-HT deficiency in gastric motility in mice and humans.<h4>Methods</h4>We developed an inducible, EC cell-specific Tph1^CreERT2/+ mouse, which was used to generate a reporter mouse line, Tph1-tdTom, and an EC cell-depleted line, Tph1-DTA. We examined EC cell distribution, morphology, and subpopulations in reporter mice. GI motility was measured in vivo and ex vivo 2021-01-01T00:00:00Z2021 Jun2025-04-19T18:19:55.259Z2025-04-19T18:19:55.259ZS-EPMC85320263366238610.1053/j.gastro.2021.02.060