Long-term hyperalimentation following hemorrhage/reperfusion injury induces intestinal prostanoid synthesis.

Intestinal mucosa and muscularis/serosa prostaglandin (PG) biosynthesis was compared in sham control female rats and rats subjected to mild hemorrhage (hemorrhage to 80 mm Hg for 60 min), blood reperfusion, and maintenance on hyperalimentation (TPN) for 5 days. Tissue PG synthesis was analyzed by radiochromatographic analysis of microsomal membrane fractions prepared from mucosa and muscularis/serosa removed from the duodenum, jejunum, and ileum. Individual PG synthesis in the mucosa and muscularis/serosa sham group was modest, with low levels of synthesis of 6-keto-PGF1 alpha, PGE2, PGF2 alpha, and thromboxane B2. Hemorrhage, reperfusion, and maintenance on TPN for 5 days did not alter PG synthesis in the mucosa, whereas muscularis/serosa synthesis of 6-keto-PGF1 alpha and PGE2 was increased five-fold or more in each tissue studied. These data suggested that the muscularis/serosa could serve as a major source for the elevated PG, previously shown to occur following long-term resuscitation after acute hemorrhage.