Protective actions of a luminally acting 5-HT receptor agonist in mouse models of colitis.

Background: 5-hydroxytryptamine 4 receptors (5-HT Rs) are expressed in the colonic epithelium, and previous studies have demonstrated that luminal administration of agonists enhances motility, suppresses nociception, and is protective in models of inflammation. We investigated whether stimulation with a luminally acting 5-HT R agonist is comparable to previously tested absorbable compounds.

Methods: The dextran sodium sulfate (DSS), trinitrobenzene sulfonic acid (TNBS), and interleukin 10 knockout (IL-10KO) models of colitis were used to test the protective effects of the luminally acting 5-HT R agonist, 5HT4-LA1, in the absence and presence of a 5-HT R antagonist.

Prokinetic actions of luminally acting 5-HT receptor agonists.

Background: 5-HT receptor (5-HT R) agonists exert prokinetic actions in the GI tract, but non-selective actions and potential for stimulation of non-target 5-HT Rs have limited their use. Since 5-HT Rs are expressed in the colonic epithelium and their stimulation accelerates colonic propulsion in vitro, we tested whether luminally acting 5-HT R agonists promote intestinal motility.

Methods: Non-absorbed 5-HT R agonists, based on prucalopride and naronapride, were assessed for potency at the 5-HT R in vitro, and for tissue and serum distribution in vivo in mice.

No Gastrointestinal Dysmotility in Transgenic Mouse Models of Migraine.

Objective: To determine whether transgenic mouse models of migraine exhibit upper gastrointestinal dysmotility comparable to those observed in migraine patients.

Background: There is considerable evidence supporting the comorbidity of gastrointestinal dysmotility and migraine. Gastrointestinal motility, however, has never been investigated in transgenic mouse models of migraine.