CHLORPROMAZINE INHIBITS PHAGOCYTOSIS AND EXOCYTOSIS IN RABBIT POLYMORPHONUCLEAR LEUKOCYTES

Phagocytosis of zymosan particles and the concomitant release of lysosomal enzymes by exocytosis in polymorphonuclear leukocytes is inhibited by chlorpromazine. Cytochalasin B prevents particle uptake, but not enzyme release; the divalent cation ionophore A 2318 7 induces enzyme release in the absence of zymosan if Ca2+ is present. In both cases enzyme release is inhibited by chlorpromazine, thus demonstrating an effect of chlorpromazine on exocytosis independent from its effect on phagocytosis. The results are discussed in relation to the role of Ca2+ in exocytosis and the effect of chlorpromazine on membrane properties. © 1979.