0000000000291242
AUTHOR
Maria-simonetta Faussone-pellegrini
GLP-2 receptor expression in excitatory and inhibitory enteric neurons and its role in mouse duodenum contractility
Background Glucagon-like peptide 2 (GLP-2), a nutrient-responsive hormone, exerts various actions in the gastrointestinal tract that are mediated by a G-protein coupled receptor called GLP-2R. A little information is available on GLP-2R expression in enteric neurons and nothing on the interstitial cells of Cajal (ICC). Methods We investigated presence and distribution of the GLP-2R in the mouse duodenum by immunohistochemistry and the potential motor effects of GLP-2 on the spontaneous and neurally evoked mechanical activity. Key Results The GLP-2R was expressed by the myenteric and submucosal neurons. Labelling was also present in nerve varicosities within the circular muscular layer an…
Peripheral motor action of glucagon-like peptide-1 through enteric neuronal receptors
Background Glucagon-like peptide-1 (GLP-1) is a proglucagon-derived peptide expressed in the enteroendocrine-L cells of small and large intestine and released in response to meal ingestion. Glucagon-like peptide-1 exerts inhibitory effects on gastrointestinal motility through vagal afferents and central nervous mechanisms; however, no data is available about a direct influence on the gastrointestinal wall. Our aim was to investigate the effects of GLP-1 on the spontaneous and evoked mechanical activity of mouse duodenum and colon and to identify the presence and distribution of GLP-1 receptors (GLP-1R) in the muscle coat. Methods Organ bath recording technique and immunohistochemistry wer…
Ultrastructural changes in the interstitial cells of Cajal and gastric dysrhythmias in mice lacking full-length dystrophin (mdxmice)
At least two populations of c-kit positive interstitial cells of Cajal (ICC) lie in the gastric wall, one located at the myenteric plexus level has a pace-making function and the other located intramuscularly is intermediary in the neurotransmission and regenerates the slow waves. Both of these ICC sub-types express full-length dystrophin. Mdx mice, an animal model lacking in full-length dystrophin and used to study Duchenne muscular dystrophy (DMD), show gastric dismotilities. The aim of the present study was to verify in mdx mice whether: (i) gastric ICC undergo morphological changes, through immunohistochemical and ultrastructural analyses; and (ii) there are alterations in the electrica…
Altered tachykinergic influence on gastric mechanical activity in mdx mice
Abstract This study investigated whether alterationsin gastric activity in dystrophic mdx mouse can beattributed to dysfunctions of tachykinins. Endolumi-nal pressure was recorded and the expression ofneuronal nitric oxide synthase (nNOS), NK1 and NK2neurokinin receptors was investigated by immunoh-istochemistry. SR48968, NK2 receptor antagonist, butnot SR140333, NK1 receptor antagonist, decreased thetone only in mdx gastric preparations. In the presenceof N x -nitro- L -arginine methyl ester ( L -NAME), inhib-itor of NOS, SR48968 reduced the tone also in normalstomach. [Sar 9 , Met(O 2 ) 11 ]-SP, agonist of NK1 recep-tors, caused tetrodotoxin-sensitive relaxations, antag-onized by SR140333…