Cell Proliferation Kinetics in Acetic Acid-Induced Gastric Ulcer Evaluated by Immunohistochemical Staining of Proliferating Cell Nuclear Antigen

A monoclonal antibody to proliferating cell nuclear antigen (PCNA) has been previously shown to be capable of identifying proliferating cells. We investigated proliferative activity in the healing process of acetic acid-induced gastric ulcer by immunohistochemical staining of PCNA and 5-bromo-2-deoxyuridine (BrdU), and the two methods were compared. Cell proliferative activity of regenerated mucosa around ulcers showed continuous acceleration for 42 days, and PCNA-labeled cells had stained nuclei as clearly discernible as those of BrdU-labeled cells. In addition, immunohistochemical staining of PCNA provided reproducible and quantifiable results without the requirement of pretreatment. We conclude that immunohistochemical staining of PCNA may represent a useful technique for analysis of proliferative activity during healing of gastric ulcers.