EXPRESSION OF HEPATOCYTE GROWTH-FACTOR IN NORMAL AND CARBON TETRACHLORIDE-TREATED MONKEYS

We examined hepatocyte growth factor-producing organs in normal and ca rbon tetrachloride-treated Japanese monkeys, a species more related to human beings than rats, by measuring hepatocyte growth factor protein and hepatocyte growth factor mRNA in various tissues. Hepatocyte grow th factor protein and hepatocyte growth factor mRNA levels were determ ined by use of an enzyme-linked immunosorbent assay for human hepatocy te growth factor and Northern-blot analysis using human hepatocyte gro wth factor cDNA as a probe, respectively. Although very slight amounts of hepatocyte growth factor protein were found in various organs of n ormal monkeys, the hepatocyte growth factor protein levels were remark ably increased only in the livers and spleens of carbon tetrachloride- treated monkeys. Hepatocyte growth factor mRNA was distinctly detected in the livers, spleens, lungs, intestinal tracts, adrenal glands and aortas of normal monkeys. After the administration of carbon tetrachlo ride, the hepatocyte growth factor mRNA levels in the liver, spleen an d gastrointestinal tract were markedly increased; the level in the lun g was unchanged, differing from the findings in rats; and the levels i n adrenal gland and aorta were unaltered. These results indicate that the liver is an important hepatocyte growth factor-producing organ in monkeys during liver regeneration and that hepatocyte growth factor in duced in the liver may stimulate hepatocyte proliferation by way of a paracrine mode.