Preventive effect of glutamine on intestinal barrier dysfunction induced by severe trauma

摘要

AIM: To investigate the mechanism underlying intestinalbarrier function damage after severe trauma and thetherapeutic effect of glutamine.METHODS: Burned patients, and animal models of severstrauma replicated by hemorrhagic shock combined withendotoxin infusion and burn injury, were included in a serialexperiment. Effects of oral glutamine on intestinal barrierfunction were observed in scalded rets. Parametersmeasured in these experiments were as follows: plasmalevels of diamine oxidase (DAO), tumor necrosis factor(TNFα), endotoxin (LPS), and lactate as well as D-lactateby biochemical methods, lactose/mannitol (L/M) ratio inurine by SP-3400, and pathological examination of intestinalmucosa under light microscopy.RESULTS: Plasma DAO activity was significantly increasedafter injury. There was a negative correlation betweenplasma DAO and intestinal mucosal DAO or pHi ( r= -0.93,plasma 0.80 ± 0.93,2.83 ± 1.71, 1.14 ± 0.64,2.36 ± 2.06 and2.49± 1.67 vs intestinal 0.52± 0.12,0.34 ± 0.03,0.45 ± 0.18,0.37± 0.26 and 0.41 ± 0.07; r = - 0.533, plasma 0.87 ± 0.75,1.89± 1.13, 1.21 ± 0.23,3.03 ± 2.61 and 4.70 ± 1.22 Vs pHi7.03± 0.05,7.05 ± 0.06,7.14 ± 0.096,7.20 ± 0.08 and 7.05 ±0.07; P ＜ 0.01-0.05). Positive correlations were foundbetween DAO activity and plasma TNFα, LPS, lactate, L/Mand D-lactate ( r = 0.817, 0.842, 0.872, and 0.951; plasmaDAO 0.87 ± 0.75,1.89 ± 1.13, 1.21 ± 0.23,3.03 ± 2.61 and 4.70± 1.22 vs TNF 0.08 ± 0.02,0.03 ± 0.25,0.17 ± 0.09,0.34 ± 0.15and 0.33 ± 0.18; vs LPS 0.14 ± 0.03,0.16 ± 0.04,0.21 ± 0.02,0.18± 0.16 and 0.37 ± 0.10; vs lactate 9.03 ± 2.19, 18.30 ±2.56,9.81 ± 2.83,12.01 ± 6.83, 12.01 ± 6.84 and 43.61 ± 11.27;vs L/M 0.03 ± 0.01,0.41 ± 0.27,0.62 ± 0.20, 1.70 ± 0.60; r =0.774, plasma DAO 1.25 ± 0.41,2.17 ± 0.71,2.29 ± 0.87, 1.23± 0.55 and 1.11 ± 0.47 vs D-lactate 8.37 ± 2.48, 18.25 ± 6.18,13.96 ± 4.94, 8.93 ± 3.00 and 12.39 ± 4.94; all P ＜ 0.01),repestively. Damage of intestinal mucosa was found bypathological examination. Intestinal barrier function wasimproved to a certain extent by oral glutamine in scaldedrats.CONCLUSION: Intestinal barrier function was damaged in theearly stage after trauma. Plasma DAO activity, D-lactatecontent, intestinal pHi and urine L/M may be sensitivemarkers of intestinal mechanical injury, and glutamine mayprotect against intestinal barrier dysfunction after severetrauma.