The cytochalasins are cell-permeable fungal metabolites that inhibit actin polymerization. This interferes with such diverse processes as cell movement, growth, phagocytosis, degranulation, and secretion. Cytochalasin H is a potent inhibitor of actin incorporation into filaments. Like cytochalasin D , it also increases the steady-state diffusion coefficients of filaments, suggesting that it stimulates filament shortening. Cytochalasin H suppresses the production of reactive oxygen species by stimulated human neutrophils, blocks endocytosis of CD59 in lymphocytes, and shows anti-angiogenic activity both in vitro and in vivo.
