NUCLEAR ACCUMULATION OF G-ACTIN IN ISOLATED RAT HEPATOCYTES BY ADENINE-NUCLEOTIDES

Extracellular ATP induces bleb formation in isolated rat hepatocytes. We examined the effect of extracellular ATP on the actin cytoskeleton of these hepatocytes, Exposure to 100 mu M ATP caused pronounced nucle ar accumulation of G-actin. ADP, AMP, adenosine, and dibutyryl-cAMP in duced the same effect, Adenosine deaminase could inhibit both ATP-and adenosine-induced nuclear accumulation, The PS-receptor agonists, UTP and 2' & 3'-O-(4-benzoylbenzoyl)-adenosine 5'-triphosphate, did not in duce this redistribution of G-actin. Phalloidin, which prevents depoly merisation of F-actin filaments to G-actin monomers, inhibited adenosi ne-induced nuclear accumulation of G-actin. These observations suggest that nuclear accumulation of G-actin is mediated by adenosine recepto rs. (C) 1997 Academic Press.