Abstract:Aim To investigate whether the all-trans retinoic acid (ATRA) will perform anti-inflammatory role and therefore to inquire into its possible mechanism of stabilizing plaques, by establishing the animal models ofcarotid artery endometrial injuring in rabbits and observing the expression level of platelet-activating factor (PAF) and leukotriene B4 (LTB4).Methods 36 New Zealand male healthy rabbits were randomly divided into three groups: contrast group (n=12), high-fat group (n=12) and treatment group (n=12), each group then were divided into three subgroups (A, B, C). Contrast group were provided basic feed while the other two groups were given fatty feed. All groups have to be suffered from artery intima air-drying technique after two weeks. Contrast group only had exposure of carotid artery but no damage to the intima others should have injury to artery intima the treatment group were administered ATRA lavage daily from 3 days before the surgery. On the 7d, 14d and 28d, the target vessels were taken out for morphological observation and measuring of intima thickening. Enzyme-linked immunosorbent assay (ELISA) method was used to detect the expression level of PAF and LTB4 in rabbit serum.Results Contrast group did not see endometrial hyperplasia, PAF and LTB4 had normal small expression. High-fat group were of endometrial hyperplasia obviously, target vessels were stenosis even deformation, PAF and LTB4 had quantity expression. The intima hyperplasia in treatment group was lower than high-fat group (P<0.05) as the same as the expression level of PAF and LTB4.Conclusion ATRA can significantly alleviate injury area endometrial proliferation, the mechanism may be related to its inhibition of PAF activation and expression, then reduce the release of inflammatory chemokines LTB4 in order to restrain the inflammatory response ultimately.