Portal hypertension-related inflammatory phenotypes: From a vitelline and amniotic point of view

Prehepatic portal hypertension induces a splanchnic low-grade inflammatory response that could switch to high-grade inflammation with the development of severe and life-threatening complications when associated with chronic liver disease. The extraembryonic origin of the portal system maybe determines the regression to an extraembryonic phenotype, i.e., vitellogenic and amniotic, during the evolution of both types of portal hypertension. Thus, prehepatic portal hypertension, or compensated hypertension by portal vein ligation in the rat, is associated with molecular mechanisms related to vitellogenesis, where hepatic steatosis and splanchnic angiogenesis stand out. In turn, extrahepatic cholestasis in the rat induces intrahepatic portal hypertension, or decompensated hypertension, with ascites and hepatorenal syndrome. The splanchnic interstitium, the mesenteric lymphatic system, and the peritoneal mesothelium seem to create an inflammatory pathway that could have a key pathophysiological relevance in the production of ascites. The hypothetical comparison between the ascitic and the amniotic fluid also allows for translational investigation. The induced regression of the splanchnic system to extraembryonic functions by portal hypertension highlights the great relevance of the extraem-bryonic structures even during postnatal life.