OBJECTIVE To compare the effects of Aloe vera and sucralfate on gastric microcirculatory changes, cytokine levels and gastric ulcer healing. METHODS Male Spraque-Dawley rats (n=48) were divided into four groups. Group1 served as control group, group 2 as gastric ulcer group without treatment, groups 3 and 4 as gastric ulcer treatment groups with sucralfate and Aloe vera. The rats from each group were divided into 2 subgroups for study of leukocyte adherence, TNF-alpha and IL-10 levels and gastric ulcer healing on days 1 and 8 after induction of gastric ulcer by 20% acetic acid. RESULTS On day 1 after induction of gastric ulcer, the leukocyte adherence in postcapillary venule was significantly (P<0.05) increased in the ulcer groups when compared to the control group. The level of TNF-alpha was elevated and the level of IL-10 was reduced. In the ulcer groups treated with sucralfate and Aloe vera, leukocyte adherence was reduced in postcapillary venule. The level of IL-10 was elevated, but the level of TNF-alpha had no significant difference. On day 8, the leukocyte adherence in postcapillary venule and the level of TNF-alpha were still increased and the level of IL-10 was reduced in the ulcer group without treatment. The ulcer treated with sucralfate and Aloe vera had lower leukocyte adherence in postcapillary venule and TNF-alpha level. The level of IL-10 was still elevated compared to the ulcer group without treatment. Furthermore, histopathological examination of stomach on days 1 and 8 after induction of gastric ulcer showed that gastric tissue was damaged with inflammation. In the ulcer groups treated with sucralfate and Aloe vera on days 1 and 8, gastric inflammation was reduced, epithelial cell proliferation was enhanced and gastric glands became elongated. The ulcer sizes were also reduced compared to the ulcer group without treatment. CONCLUSIONS Administration of 20% acetic acid can induce gastric inflammation, increase leukocyte adherence in postcapillary venule and TNF-alpha level and reduce IL-10 level. Aloe vera treatment can reduce leukocyte adherence and TNF-alpha level, elevate IL-10 level and promote gastric ulcer healing.