Quantitative determination of poly(adenosine diphosphate ribose) in different hepatic tissues by an isotope dilution procedure.

A procedure has been developed for the quantitation of poly(ADP-ribose) in intact tissues. It is based on the dilution of added [3H]poly(ADP-ribose) by the endogenous polymer. 5 - 6 nanomoles protein-bound ADP-ribose per mg DNA were found in adult and neonatal rat liver, while Zajdela hepatoma cells had significantly lower values. A comparison with mono(ADP-ribose) residues in adult rat liver revealed similar levels of monomeric and polymeric ADP-ribose residues. This means that far more proteins (or acceptor sites on proteins) must be occupied by single ADP-ribose residues than by oligo or poly(ADP-ribose) chains. While the poly(ADP-ribose) levels of the different tissues do not correlate with the corresponding proliferation rates, the amount of mono(ADP-ribose) does show a certain Correlation, being low in rapidly growing tissues.