FLOW CYTOMETRIC ANALYSIS OF CELL-PROLIFERATION KINETICS DURING DUODENAL-ULCER HEALING

Cell proliferation in the gastroduodenal mucosa of patients with duode nal ulcers was evaluated using flow cytometry. Forty patients with duo denal ulcers and 12 normal subjects were investigated. Biopsy samples were obtained during endoscopic examination and subjected to DNA analy sis by flow cytometry. Thirty patients with duodenal ulcers were heale d within 3 months with H-2 blockers (tractable or responsive ulcers), whereas 10 patients did not respond to treatment (intractable ulcers). The percentage of cells at the DNA-synthetic phase, an index of cell proliferation, was constant in the adjacent duodenal mucosa 2 cm from ulcer margin and antral mucosa during duodenal ulcer healing. The inde x at the margin of tractable ulcers was elevated during the active sta ge (12.9 +/- 1.3), peaked during the healing stage (15.4 +/- 2.8) and returned to the same level at the scarring stage (10.9 +/- 2.0) as nor mal controls (10.3 +/- 1.7). However, the index was not elevated in in tractable ulcers (10.3 +/- 1.7 in the healing stage) and was smaller t han in tractable ulcers. These data indicate that augmented mucosal ce ll proliferation at the ulcer margin plays an important role in duoden al ulcer healing and intractable ulcers are characterized by an abnorm al failure to accelerate DNA synthesis to achieve ulcer repair.