Effects of hydrochloric, valeric, and other volatile fatty acids on pathogenesis of ulcers in the nonglandular portion of the stomach of horses.

This study investigates the impact of various acids, including hydrochloric and valeric acid, on the formation of ulcers in the non-glandular area of a horse’s stomach. The results highlight that valeric acid, particularly in conditions of pH less than or equal to 7.0, significantly diminishes the mucosal barrier function, potentially contributing to ulcer development.

Research Methodology

• The study was conducted using gastric tissues from 13 adult horses. The chosen portion of the horse’s stomach for the experiment was the nonglandular gastric mucosa.
• The Ussing chambers technique was applied in this study. This method is commonly used for the measurement of trans-epithelial electric current in a section of tissue.
• The impact of acids on the tissues was measured through observing changes in short-circuit current (Isc), potential difference, and calculating resistance and conductance.
• Different acids used for testing were hydrochloric, valeric, acetic, propionic, and butyric acids. During the experiment, these acids were added to a normal Ringer’s solution (NRS) which bathed the tissues.
• The tissue samples were later examined under a microscope for histological studies.

Findings

• Valeric acid, at a concentration of 60mM and pH level of less than or equal to 7.0, was found to dramatically and irreversibly remove the short-circuit current (Isc). This was later followed by a decrease in resistance and an increase in conductance.
• Other tested acids – including acetic, propionic, and butyric acids, also led to a significant decrease in Isc at the same pH level and concentration. However, these changes were followed by a rise in resistance and a drop in conductance.
• The changes brought about by valeric acid were also linked to notable histopathological evidence of cellular swelling across all layers of the examined tissues.

Conclusions

• The notable reduction in the stomach’s mucosal barrier function due to valeric acid indicated a direct link to ulcer formation in the nonglandular area. This also suggested that the acid disrupts sodium transport within the cells, resulting in cellular swelling.
• Given the high lipid solubility of valeric acid, it can permeate the nonglandular gastric mucosa, potentially explaining the observed ulcerative effects.
• The researchers concluded that valeric acid and potentially other volatile fatty acids present in gastric contents might play a significant role in the formation of ulcers within the nonglandular area of a horse’s stomach.