ObjectiveTo explore the protective effect of low-molecular-weight heparin calcium (LHC) combined with trimetazidine on intestinal smooth muscle of intestinal acute mesangial vein thrombosis (AMVT) in rats and it's mechanism of effect. MethodsA total of 120 SD male rats were randomly divided into three groups, with 40 rats in each group. LHC group: after the AMVT model established, rats were subcutaneous injection the LHC (30 U/100 g) per 12 h until 72 h after surgery. LHC+trimetazidine group (LHCT group): after the AMVT model established, rats were subcutaneous injection the LHC (30 U/100 g) and tail vein injection the trimetazidine (10 mg/kg) per 12 h until 72 h after surgery. Normal saline group (NS group): after the AMVT model established, rats were subcutaneous injection the NS (0.2 mL/100 g) per 12 h until 72 after surgery. The AMVT model were established by blocking superior mesenteric vein of 8 cm and the edge vein arch. Vena cava blood samples and intestinal segments were collected sequentially at 6 h, 12 h, 24 h, 48 h and 72 h afrer surgery. The levels of malondialdehyde (MDA) and creatine kinase (CK) in the blood, and the level of ATP in the intestinal tissue samples were measured with ELISA. Intestinal tissue were taken from the rats for inestinal tissue section, stained with hematoxylin and eosin, examined under light microscopy and evaluated histopathologically using mesemeche scoring system at different time. ResultsCompared with the LHC group and NS group, the levels of MDA and CK in blood and histopathology score of intestinal tissues in rats were significantly decreased, and the level of ATP significantly increased in LHCT group at different time point (P < 0.05). ConclusionTrimetazidine can improve intestinal smooth muscle energy metabolism in the AMVT disease, comined with LHC early can avoid intestinal smooth muscle wall permeability coagulation necrosis and reduce the intestinal smooth muscle damage.