Role of intestinal microflora and insufficient barrier function of the liver in the development of endotoxinemia and inflammation

The role of the saprophytic intestinal microflora is not limited to participation in the digestive process. Endotoxin (an obligatory component of the cell membrane of all Gram-negative bacteria) released as a result of self-renewal of the E. coli cell pool enters the portal bloodstream and performs antigenic stimulation of the macroorganism. In addition, a small amount of endotoxin can also be released by live Gram-negative bacteria, which under conditions of numerous E. coli populations in the intestine can create a fairly high concentration of endotoxin. It is possible that this is why the normal concentration of endotoxin in the blood of the intact rat portal vein is 5 ng/ml, although in humans it is much lower. It is believed that under physiological conditions all endotoxin is eliminated from portal blood by hepatic Kupffer cells.