Selective changes in protein kinase C isoenzymes in rat liver nuclei during liver regeneration.

Using isoenzyme-specific antisera, protein kinase C (PKC) alpha and PKC delta were detected in total liver homogenate and in isolated nuclei. PKC beta I, beta II, epsilon, epsilon', and zeta were not detected. During liver regeneration, nuclear PKC alpha levels decreased while PKC delta levels increased. These studies demonstrate, for the first time, the presence of a calcium-independent PKC isoenzyme in liver nuclei and suggest that PKC alpha and PKC delta may have different roles in liver regeneration and cell proliferation.