Irradiation and gastro-intestinal fibrinolysis: an experimental study in the rat.

Tissue fibrinolysis in the rat stomach and transverse colon was studied after X-ray irradiation of the abdomen. Tissue biopsies were examined on unheated fibrin plates and with a histochemical technique modified from Todd. A significantly increased fibrinolytic activity was found in the mucosa of the stomach and colon 3 days after irradiation, while fibrinolysis localized to submucosal vessels was unchanged. Mucosal fibrinolysis in the stomach was significantly inhibited by intragastric administration of tranexamic acid.