PHOSPHOINOSITIDE SIGNAL-TRANSDUCTION PATHWAY DURING REGENERATION FOLLOWING PARTIAL-HEPATECTOMY

Phosphorylation of endogenous phosphatidylinositol was transiently inc reased following partial hepatectomy but was suppressed during peak DN A synthesis. Formation of inositol trisphosphate was decreased while g eneration of diacylglycerol and its breakdown to phosphatidic acid was increased. In response to partial hepatectomy protein kinase C was ac tivated due to translocation from cytosol to particulate fraction, but the membrane bound activity was decreased during regeneration. Altera tion of certain parameters in the signal transduction pathway apparent ly facilitates cell proliferation.