Kinetics of expression of connective tissue growth factor gene during liver regeneration after partial hepatectomy and D-galactosamine-induced liver injury in rats

Connective tissue growth factor (CTGF) it regulated by TGF-beta1 during wou nd healing. The present study examined the expression of CTGF during regene ration after 70% partial hepatectomy (PH) or D-galactosamine (GalN)-injured liver in rats. CTGF, TGF-beta1, and type I collagen mRNAs were semiquantif ied by a ribonuclease protection assay. After PH, TGF-beta1 and type I coll agen were increased at 2-6 h and at 12-48 h. CTGF increased at 6 h and retu rned to the control level thereafter. The ribonuclease protection assay of cultured hepatic stellate cells (HSC) and in situ hybridization suggest tha t the cells express CTGF along sinusoid might be HSCs. After GalN administr ation, CTGF increased at 2-96 h with a shoulder peak at 6-12 h followed by a main peak at 24 h. TGF-beta1 and type I collagen were up-regulated with k inetics similar to those of CTGF. The different kinetics between PH and Gal N regenerations indicate that regulation of CTGF in the two processes is di fferent. Higher TGF-beta1 expression after inflammatory/necrotic process in the GalN regeneration may caused the prolonged CTGF expression. (C) 2000 A cademic Press.