Abstract： Objective To investigate the effects of somatostatin(SST)or vasoaetive intestinal peptide (VIP)on the expression of MAdCAM-1 in the intestinal muecosa of rats with multiple organ dysfunction syndrome (MODS)and its significance of prevention and treatment of MODS.Method Thirty six Wistar male rats were randomly divided into 6 groups(6 rats in each group),including control group,VIP group 1 and SST group1 (rats treated with VIP and SST respectively),MODS group(rats with MODS),VIP group 2 and SST group 2(NODS rats treated with VIP and SST respectively).The rat model of MODS(system inflammatory response syndrome,＞2 or-gans dysfunction)was established by occlusion of superior mesenteric arteries.0.2 ρmol·g-1 h -11 VIP or SST by intravenous injection combined with 0.25 ρmol/g VIP or SST by intraperitoneal injection were injected into rats.In each group,intestinal lymphocytes from rats labeled with 51 Cr were infused into rat veins and were quantified with γcounter in GALT.The expression of MAdCAM-1 in the intestinal mucosa was measured by western blot.Inflam-mation in the intestinal mucosa was evaluated with histological sections.Student's t test was used to assess differ-ence between the experiment group and the control group.Results In VIP group l and SST group 1,the peak values of MAdCAM-1 expression in diffusive lymphatic tissue of small intestinal were 157.67±2.52 and 154.33±3.22.and those in Peyer patches were 136.00±1.00 and 137.00±1.00.There were no significant difference when compared with control group(165.33±1.53,152.67±2.31,P＞0.05).The percentage of 51 Cr-lympho-cytes in diffusive lymphatic tissue of small intestine(1.04%±0.59%,1.01%±0.83%)showed no significant difference from control group(1.07%±0.61%,P＞0.05),and those in Peyer patches(1.83%±0.90%,1.56%±0.64%)were significantly less than control group(3.85%±2.02%,P＜0.05).In VIP group 2 and SST group 2,the peak values of MAdCAM-1 expression in diffusive lymphatic tissue of small intestinal(158.00±2.65,154.33±1.53)and Peyer patches(156.33±1.53.151.33±2.31)were significantly less than MODS group(175.33±2.52,173.00±2.65,P＜0.05).The percentage of 51 Cr-lymphocytes in diffusive lymphafic tissue of small intestine(1.58%±0.42%,1.45%±0.26%)and Peyer patches(2.14%±1.49%,0.81%±0.35%)were significantly less than MODS group(3.23%±1.69%,5.04%±1.23%,P＜0.05)and the se-vere histopathological danlage in intestine was relieved.Conclusions VIP or SST reduced intestinal lymphoeytes homing to GALT in rats with MODS through suppressing the expression of MAdCAM-1,and attenuated the inflam-matory injure in the intestinal mucosa.