Zinc increases phorbol ester receptors in intact B-cells, neutrophil polymorphs and platelets

AbstractIn the presence of pyrithione, which was used as a Zn2+ ionophore, Zn2+ (10–100 μM) increased phorbol ester binding by intact B-CLL cells in a dose-dependent fashion. Zn pyrithione increased 2-fold the number of phorbol ester receptors in B-cells (0.74 to 1.4 pmol/106 cells), neutrophil polymorphs (0.2 to 0.51 pmol/106 cells) and platelets (91 to 209 pmol/1010 cells). Fractionation of cells after treatment with Zn pyrithione showed that increased binding of PDBu occurred in the particulate fraction of cells and this was accompanied by loss of phorbol ester receptors from the cytosol. These data are compatible with a role for Zn in the subcellular distribution and activation of protein kinase C