Expression and induction of anaphylatoxin XXXX receptors in the rat liver.

@entity19886 @entity558 @entity82 @entity7311 @entity568 @entity2918 @entity45846 @entity1810 @entity413
The @entity7311 -anaphylatoxin which is generated by limited proteolysis upon activation of the fifth component of complement may be induced by the classical, the alternative or the lectin pathway. @entity7311 has been shown, under normal conditions, to induce the release of @entity2918 from Kupffer cells (KC) and hepatic stellate cells (HSC) and thereby indirectly to increase @entity413 output from hepatocytes (HC). A direct action of @entity7311 on HC would require the expression of the specific @entity19886 ( @entity19886 ). In studies using quantitative RT-PCR it was shown that non-stimulated HC lack @entity19886 , in contrast to KC, HSC and sinusoidal endothelial cells (SEC) all of which contained mRNA for the @entity19886 in decreasing amounts. FACS analyses, immunohisto- and immunocytochemistry as well as functional analyses confirmed the results of the RT-PCR assays. Under inflammatory situations the @entity19886 was found to be upregulated in various organs and tissues which included the liver. @entity568 ( @entity568 ) as a main inflammatory mediator in the liver induced a de novo expression of functional @entity19886 in HC in-vitro and in-vivo. In contrast, @entity558 failed to induce @entity19886 directly in cultured HC in-vitro but induced @entity19886 in HC in vivo and in co-cultures of HC and KC which release @entity568 upon stimulation with @entity558 . So far, the only known effector function of @entity7311 on HSC was the induction of prostanoid release. In an approach to reveal new functions of @entity19886 in HSC, the cells responsible for liver @entity82 , it could be shown that @entity7311 upregulated fibronectin-specific mRNA five-fold whereas @entity45846 , collagen IV and the structure protein smooth muscle actin were not affected. In addition, @entity7311 did not upregulate specific mRNA for the profibrotic cytokine @entity1810 in either isolated KC or HSC. Thus, @entity7311 alone appears to have only a limited role in the induction of liver @entity82 .
