RESUMO
Objective To observe the effects of ganoderma lucidum polysaccharide(GLP) on intestine mucosal barrier function and tumor necrosis factor-α(TNF-α)in hemorrhagic shock rabbits. Methods Thirty healthy Japanese white rabbits were divided into three groups by random number table:sham operation group, resuscitation/reperfusion with normal saline(NS)group(NS group)and resuscitation/reperfusion with GLP group (GLP group). The hemorrhagic shock models were reproduced by being bled from the femoral artery to the mean arterial pressure(MAP)of 30-40 mmHg(1 mmHg=0.133 kPa)within 10 minutes and kept maintaining at this MAP level for 40 minutes. Then,the anti-shock therapy was given. The rabbits in NS group were immediately and quickly resuscitated with reperfusion of their shed blood and intravenous drip of NS in a volume equal to 2-fold of the volume of the shed blood. The rabbits in GLP group were dealt with the same means as NS group except NS was replaced by 1%GLP. The rabbits in sham operation group were only cannulated and maintained in a status of blood pressure measurement,but without bloodletting and resuscitation. The TNF-α content,the number of positive bacterial culture of blood bacteria were observed at the time before shock(S0),40 minutes after shock(S40)and 40 minutes and 90 minutes after resuscitation/reperfusion(R40,R90),respectively in the three groups. The serum endotoxin level and the TNF-αcontent in intestinal mucosa were examined at R90. Under the light microscopy,the pathological changes of intestinal mucosa were examined,and the score of the mucosal damage was evaluated by the criteria of Chiu method. Results ①Before shock,the results of blood bacterial culture of all animals in three groups were negative. With the extension of time,the positive rates of blood bacteria were increased gradually at R40 and R90 in NS and GLP groups,showing increment of bacterial translocation,but the levels at R40 and R90 were significantly lower in GLP group than those in NS group at the same time points(number of rabbits at the time of R40:2 vs. 4,at the time of R90:4 vs. 6,both P<0.05). Escherichia coli was the most common positive bacteria in the blood;the other positive bacteria were sequentially less and less,Enterococcus,Lactobacillus acidophilus and Staphylococcus aureus. Compared with sham operation group,the serum endotoxin levels of NS and GLP groups were significantly higher at R90(kU/L:1.823±0.963,1.361±0.529 vs. 0.064±0.036,both P<0.05). ② Under the light microscope,it was shown that in NS group the mucosal villi were edematous,the sub-epithelial space was widened,and there was infiltration of neutrophils and lymphocytes. The damage of intestinal mucosa in GLP group was obviously milder than that in the NS group. The Chiu scores of GLP and NS groups were significantly higher than that of sham operation group;meanwhile,Chiu score of GLP group was lower than that of NS group(1.44±0.64 vs. 3.79±1.23,P<0.05).③Along with extension of ischemia and reperfusion time,TNF-α contents in NS and GLP groups were gradually increased significantly,the peak value being at R90,meanwhile,the levels in both groups were significantly higher than the level of sham operation group,and the TNF-α content in plasma of GLP group was lower than that of NS group〔A value:33.350±7.950 vs. 85.080±4.330,P<0.05〕. Compared with sham operation group,the TNF-αcontents in intestinal mucosa of NS and GLP groups were higher than the level in sham operation group,meanwhile,TNF-αcontent in intestinal mucosa of GLP group was lower than that of NS group〔A value:96.38±8.59 vs. 167.73±12.32, P<0.05〕. Conclusion In the salvage process of resuscitation-reperfusion,GLP can protect intestinal barrier function in rabbits with hemorrhagic shock,and its effect may be related to antagonizing the release of TNF-α.