RESUMO
Ulcer healing process is an intricate and active process including reconstruction process of mucosa through formation of granulation tissue. Granulation tissue formation takes place by means of formation of ulcer base, formation of blood vessel (angiogenesis) and re-establishment of glandular architecture. The process of granulation tissue formation on the ulcer base takes place 48-72 hours after ulceration process occurs. These three phases involve various genes grouped according to their activated time, i.e. the initial response genes, intermediate response gene and late response genes. Initial response genes are activated in 30 minutes to 2 hours time, e.g EGF-R, c-fos, c-jun, egr-1, Sp-1, TFF-2/SP. Intermediate response genes are activated for 6 hours to 2 days, eg EGF, bFGF, PDGF and VEGF. Late response genes are activated for 14 days, e.g. HGF, ITF, c-met/HGF-R.