[Changes in amine contents and regulating enzyme activity of gastric mucosa during the healing process of acetic acid induced ulcer in rats].

Changes in the contents of various amines and histidine decarboxylase (HDC) activity in the gastric mucosa during the healing process of acetic acid induced gastric ulcer in rats were sequentially examined in the ulcer region and intact region at 2, 10, 40, 80, 180 and 365 days after the operation. The following results were obtained: 1) Histamine (HA) content in the ulcer region was decreased as compared with the intact region at 2 and 10 days and returned to the control level in 40 days. After 180 days, the contents in the ulcer region and intact region were also increased as compared with that of the normal control region. 2) Changes in serotonin (5-HT) content as well as HA content were observed. 3) Norepinephrine content in the ulcer region was decreased as compared with the intact region at 2, 10, 80 and 180 days. 4) HDC activity in the ulcer region was decreased as compared with the intact region at 2, 10 and 40 days, and a lower level was maintained still at 180 days. 5) In the relapse and recurrence of gastric ulcer at 365 days, HA and 5-HT contents in the intact region and ulcer region were not different from those in healing rats, but the contents of these amines were higher at 180 days. The results suggest that the change of HA, 5-HT contents and HDC activity in the gastric mucosa may be one of the factors involved in the relapse and recurrence of chronic ulcers.