EFFECTS OF EPITHELIAL PROLIFERATION AND DIFFERENTIATION ON ULCER HEALING

Factors in ulcer healing: Traditionally, the equation of ulcer formati on and healing includes damaging agents on one hand, and mucosal defen ce, with acid inhibition, Helicobacter pylori eradication and cell pro liferation and differentiation, on the other. Relatively few studies i n cell proliferation and differentiation have been concerned with ulce r healing. The mucosa of the gastrointestinal tract consists of epithe lial cells disposed in proliferative units which have a basically simi lar kinetic architecture. When the mucosa is damaged, the regenerative processes involves the migration of surviving epithelial cells over a ny mucosal defect so formed. The phenotype of these migrating cells su ggests that they are related in some aspects to the mucous neck cell l ineage. Effects of cell division and proliferation: Cell division is u sually considered to be an important part of this regenerative process , as emphasized by findings in non-steroidal anti-inflammatory drug-in duced gastric and duodenal ulceration which have shown that the mucosa around this type of mucosal defect undergoes prominent reduction in c ell proliferation, which may contribute to the duration of the lesions . Another, very much neglected, component of the healing process is th e phenomenon of crypt and glandular fission. A further, little-studied aspect of ulcer healing is the induction, in chronically ulcerated mu cosa, of an ulcer-associated cell lineage that secretes a host of pept ides with growth-regulatory properties. Conclusion: Cell proliferation and differentiation are important but under-investigated components o f ulcer healing.