BASIC FIBROBLAST GROWTH-FACTOR IS HEPATOTROPIC FOR RAT-LIVER IN REGENERATION

A role for fibroblast growth factor in liver regeneration has recently been suggested, In this study we followed the intravenous delivery of recombinant human [I-125]basic fibroblast growth factor to the liver of rats following 68% partial hepatectomy, The concentration of [I-125 ]basic fibroblast growth factor was higher in the liver (mean+/-SD, 6. 8+/-0.8 9% of injected dose) and the kidney (6.7+/-0.2%) of sham-opera ted rats than in the spleen (2.8+/-0.45%). It increased threefold in t he liver only, soon after 68% partial hepatectomy (20.3+/-5.3%, p<0.00 1), and remained high for the first 24 h. We also studied the effect o f basic fibroblast growth factor injection on the rate of [H-3]thymidi ne incorporation into liver DNA in rats subjected to either 21% or 68% partial hepatectomy. A significant increase was seen after intramesen teric injection of 500 ng basic fibroblast growth factor into rats sub jected to 21% partial hepatectomy (23.5+/-7.3 cpm/mu g DNA) compared t o saline-injected rats (14.5+/-6.4 cpm/mu g DNA, p=0.034). A dose of 5 000-25000 ng injected into a peripheral vein resulted in higher thymid ine incorporation than in saline-injected control rats (36.9+/-12.7 an d 9.7+/-6.1 cpm/mu g DNA, respectively; p<0.0001). No significant effe ct was seen after 68% partial hepatectomy, Autoradiography showed that the hepatocytes were the predominant labelled cells early after hepat ectomy and basic fibroblast growth factor injection, We conclude that basic fibroblast growth factor uptake by the liver is increased after 68% partial hepatectomy and that basic fibroblast growth factor is mit ogenic to liver parenchymal cells early after 21% partial hepatectomy.