Subserosal application of transforming growth factor-beta 1 in rats with chronic gastric ulcers: effect on gastric ulcer healing and blood flow.

Transforming growth factor beta 1 (TGF-beta 1) has been shown to play a central role in wound healing. This peptide has been detected in the stomach, but no information is available at present whether TGF-beta 1 influences the healing of gastric ulcers and whether the mucosal expression of TGF-beta 1 changes in the course of this healing. In this study, gastric ulcers were induced by serosal application of acetic acid and TGF-beta 1 or vehicle saline was injected twice into the subserosa around the ulcer area, once immediately after ulcer induction and two days later. Local application of TGF-beta 1 led to significant acceleration of gastric ulcer healing. Gastric blood flow at the ulcer margin was significantly higher than that in the ulcer crater but no significant difference was found in this flow between studied groups. Immunohistochemistry showed that the expression of TGF-beta 1 reached the peak at day 2 and then declined in the course of healing. We conclude that TGF-beta 1 accelerates ulcer healing possibly by increasing the formation of granulation tissue and cell migration probably mediated by locally expressed TGF-beta 1 but the healing effects of TGF-beta 1 do not depend on the vascular factor.