Effects of hydrochloric, acetic, butyric, and propionic acids on pathogenesis of ulcers in the nonglandular portion of the stomach of horses

Abstract

Acetic, butyric, and propionic acids and, to a lesser extent, HCl caused decreases in mucosal barrier function of the nonglandular portion of the equine stomach. Because of their lipid solubility at pH < or = 4.0, undissociated VFAs penetrate cells in the nonglandular gastric mucosa, which causes acidification of cellular contents, inhibition of sodium transport, and cellular swelling. Results indicate that HCl alone or in combination with VFAs at gastric pH < or = 4.0 may be important in the pathogenesis of gastric ulcers in the nonglandular portion of the stomach of horses.

Efecto del aceite de maíz sobre los ácidos grasos volátiles en caballos con úlceras gástricas inducidas

“…Specifically, at a pH lower than 4, VFA accentuate the alterations in the non-glandular mucosa area of the equine stomach, specifically la curvatura menor (5,6). En este trabajo, posiblemente la perpetuación de las lesiones en la área no glandular de la mucosa fueron derivadas de la no ionización de los AGV analizados (acético, butírico y propiónico), por el pH bajo del contenido gástrico que osciló entre 2.38 y 3.77 en los grupos tratados con aceite de maíz, donde no cicatrizaron las úlceras en su totalidad.…”

“…Furthermore, it is likely that the total VFA concentration had also been changed by volatilization processes prior to the collection or by transformation to carbon dioxide, β-hydroxybutyrate, and acetoacetate, which normally occur with these acids (5). In addition, the animals in this study were fed a diet low in fermentable carbohydrates (approximately 2.5 kg of concentrated and distributed on average twice/day), unlike other studies where these types of carbohydrates were used (13).…”

“…However, as shown in the control group, the effect of confinement may have had a greater action on the gastric ulceration in the horses than PBZ. However, it is also necessary to consider that VFA have ulcerogenic effects in the equine stomach (5,7) and are altered in horses with right dorsal colitis induced by PBZ (20).…”

“…Los ácidos grasos volátiles (AGV) como el butírico, propiónico, acético y valérico, son derivados de procesos fermentativos de carbohidratos por bacterias gástricas; sin embargo, los AGV han sido relacionados a producir "in vitro" lesiones en la mucosa no glandular de equinos (5,6). Sin embargo, en un estudio se determinó variadas concentraciones de AGV en el contenido gástrico de caballos alimentados con dietas a base de heno o combinación de heno y concentrado que no influyeron en la aparición de úlceras gástricas (7).…”

“…VFA have been found to produce "in vitro" lesions in the non-glandular mucosa of the equine stomach (5,6). However, in an early study it was observed that varying concentrations of VFA in stomach contents of horses fed diets based on hay or hay plus concentrate did not influence the appearance of gastric ulcers in these animals (7).…”