Gastric mucosal cytoprotection in the rat by naftidrofuryl oxalate

Serotonin-Containing Cells in the Gastrointestinal Tract of Newborn Foals and Adult Horses

Serotonin (5-hydroxytryptamine, 5-HT), a regulatory amine of mucosal enterochromaffin cells plays an important role in the control of gastrointestinal smooth muscle contraction and epithelial secretion. Serotonin has also been associated with gastric ulcers, diarrhoea and abdominal pain. In spite of the high incidence of these gastrointestinal disorders in newborn foals and adult horses, no data are available regarding 5-HT immunoreactive cells (i.c.) in the gastrointestinal tract (GIT) of foals, and for adult horses, data are incomplete and contradictory. In this study, the distribution and relative frequency of 5-HT i.c. in the GIT of newborn foals and adult horses were determined immunohistochemically. In foals as in adults, a relatively large number of 5-HT i.c. were detected in all portions of the GIT. In foals, a significantly higher amount of cells was found in the pyloric region and margo plicatus of the stomach, as well as in the caecum and colon ascendens compared with adults. Our results provided rationale for further research concerning the role of 5-HT i.c. during the milk diet or in the regulation of gastrointestinal growth/cell proliferation, and in the pathogenesis of gastric ulcers, especially in newborn foals.

Naftidrofuryl protects the rat against chronic gastric ulceration

Intraperitoneal reserpine (5 mg/kg every day for 5 days) produced solitary chronic ulceration of the rat stomach after 2 weeks. Gavage with 1 mL/day of 1% naftidrofuryl oxalate for 2 weeks protected 30% of rats against ulceration and this protection extended to 70% of cases with a 2% solution. Similar gavage with a 5% solution protected all rats against ulceration without significantly influencing the basal H+ output (14.8 +/- 0.6 versus 15.4 +/- 0.5 mumol, mean +/- SEM, n = 10); that is, cytoprotection was achieved.