Characterization and Distribution of Interstitial Cells of Cajal in Healthy Stomachs of Equids: A Comparative Study between Species (Horses, Donkeys and Mules)
Articles in Press, Accepted Manuscript, Available Online from 08 August 2026
Angie Lorena Medina Bolivar, Julian David Muñoz Duque, Jose Ramon Martinez Aranzales
Abstract Interstitial cells of Cajal (ICC) play a crucial role in regulating gastrointestinal motility, functioning as pacemakers in the digestive system of equids. This study described and compared the ICC populations in different regions of the stomachs of equids (horses, donkeys and mules). A total of 30 healthy stomachs from horses, donkeys, and mules were evaluated using immunohistochemistry and high-resolution microscopy to assess various regions of the stomach in these species. The results showed the presence of ICC in all three equid species, with a predominance in the submucosa across the squamous mucosa, glandular mucosa and pyloric antrum. The density and morphology of ICC varied slightly between species, although no significant differences were found. Among the equids studied, donkeys showed the lowest ICC density, while horses exhibited the highest in the evaluated tissues. Four cellular morphologies were identified, three of which were included in the analysis, as toluidine staining revealed that one corresponded to mast cells. Further studies are needed to elucidate dynamics and possible alterations in response to gastric pathologies.