Details

Autor(en) / Beteiligte

• Marker, Alison J.
• Galloway, Euan
• Pamer, Susan
• Nakamura, Toshikazu
• Gould, Ggwyn W.
• Macsween, Roderick N.M.
• Bushfield, Mark

Titel

Role of the adenylate cyclase, phosphoinositidase C and receptor tyrosyl kinase systems in the control of hepatocyte proliferation by hepatocyte growth factor

Ist Teil von

• Biochemical pharmacology, 1992-09, Vol.44 (6), p.1037-1043

Ort / Verlag

New York, NY: Elsevier Inc

Erscheinungsjahr

1992

Quelle

Elsevier Journal Backfiles on ScienceDirect (DFG Nationallizenzen)

Beschreibungen/Notizen

• Hepatocyte growth factor (HGF) is the most potent known mitogen for hepatocytes in primary culture. However, the mechanisms through which HGF induces hepatocyte proliferation have not been defined. Here we have investigated the role of the adenylate cyclase, phosphoinositidase C and tyrosine kinase signalling systems in the control of hepatocyte proliferation by HGF using freshly isolated or cultured adult rat hepatocytes. We show that human recombinant HGF caused a dose-dependent increase in hepatocyte DNA synthesis with a maximal effect at 10 ng/mL and an ec 50, of 5.9 ng/mL. HGF had no effect on hepatocyte adenylate cyclase activity or intracellular cAMP levels. Elevation of hepatocyte cAMP levels resulted in inhibition of HGF-stimulated DNA synthesis. HGF stimulated inositol phospholipid hydrolysis with a maximal effect at 25 ng/mL and potentiated the effect of vasopressin (10 −8 and 10 −9M). HGF (100 ng/mL) caused an increase in the phosphorylation on tyrosine of an unknown hepatocyte protein with a molecular mass of 36 kDa. Thus, we have shown that HGF, like epidermal growth factor (EGF), can activate the phosphoinositidase C and tyrosine kinase systems in rat hepatocytes. As with EGF, these intracellular signalling systems may underlie HGF-induced hepatocyte proliferation.