[A study on expression of fibronectin receptor alpha 5 beta 1 of Ito cells in experimental liver fibrosis in rats].

OBJECTIVE

The study was designed to study the role of fibronectin (FN) receptor alpha 5 beta 1 in liver fibrogenesis.

METHODS

Northern blot analysis and immunohistochemical techniques were used to observe the in vivo and in vitro changes in the expression of FN and its receptor alpha 5 beta 1 in CCl4 induced rat liver fibrosis in Ito cells.

RESULTS

(1) alpha 5 beta 1 was mainly detected in the endothelia and some of the desmin (DM) positive cells (Ito cells) of the sinusoids in normal rat liver. The expression of alpha 5 beta 1 of DM positive cells in the experimental groups was enhanced and reached their peaks by the 10th week. The changes in FN was similar to that of alpha 5 beta 1; (2) The expression of FN, alpha 5 and beta 1 mRNA of the liver in the experimental groups detected by Northern blot analysis was increased and reached their peaks by the 6th week. The content of these mRNAs of the cultured Ito cells isolated from the experimental group was increased more than that from normal liver specimens.

CONCLUSION

Ito cells expressed FN receptor alpha 5 beta 1. The activation of Ito cells resulted in the increase of the expression of the three mRNAs during fibrogenesis. It is suggested that the detection of gene transcription of FN and its receptor mRNAs by Northern blot analysis could reveal the activation and proliferation of Ito cells and thereby provides a sensitive signal of liver fibrosis.