Protein kinase C activators inhibit the antigen receptor-coupled polyphosphoinositide phosphodiesterase in murine B lymphocytes

Protein kinase C activators (e.g. PMA) inhibit the inositol phosphate release generated by crosslinking antigen receptors (sIgM and sIgD) on murine B lymphocytes with anti-receptor antibodies. Unlike other Ca2+-mobilizing receptor systems, the antigen receptor signal transduction pathway in B cells is not interrupted by PMA at the level of receptor/G-protein or G-protein/polyphosphoinositide phosphodiesterase coupling. In these cells, PMA, presumably by activating protein kinase C, inhibits inositol phosphate release by direct effects on the polyphosphoinositide-specific phosphodiesterase.