Experimental Study on the Mechanism of Protective Effect of Free Fu on Gut-derived Endotoxin-Mediated Lung Damage

摘要

The effect of tumor necrosis factor-α (TNF-α) on endotoxin (ET)-mediated lung damage caused by incomplete ligation of large intestine and the influence of free Fu on the expression of TNF-α mRNA were explored. Forty SD rats were randomly divided into 4 groups: normal control group, model group, ligation group and treatment group (n=10 in each group). The models were made by the method of partly ligating the rectum outside the body. The plasma level of lipopolysac-caride was measured by dynamic nephelo metric method and the serum level of TNF-α was detected by the method of radioactive immunity. The expression of TNF-α mRNA in lung tissue was detected by RT-PCR method. The results were compared among the 4 groups. The results showed the plasma levels of ET and serum TNF-α in the model group and the expression of TNF-α mRNA in the lung tissues were remarkably higher than those in the normal control group (P < 0. 01). After the treatment of free Fu, all of the above indexes in the treatment group were all decreased as compared with model group (all P < 0. 01), and the damage to lung was alleviated. It was concluded that TNF-α might play a very important role in the ET-mediated lung damage caused by incomplete ligation of large intestine, free Fu could protect the lung from damage.