Endotoxin
is a metabolite of Gram-negative bacteria and is part of the composition
of their cell wall; diamine oxidase is an endocellular enzyme of the
villous cells of mammalian mucous membranes; and D-lactate is a
metabolite of bacterial fermentation. Under normal circumstances, no
endotoxin, diamine oxidase, or D-lactate can pass through the epithelial
mucosa, and their presence in blood is an indicator of intestinal
permeability (Luk et al., 1983). In