硫酸長春新堿抑制劑Vincristine binds irreversibly to microtubules and spindle proteins in S phase of the cell cycle and interferes with the formation of the mitotic spindle, thereby arresting tumor cells in metaphase. Vincristine Sulfate is the sulfate salt of a natural alkaloid isolated from the plant Catharanthus roseus (Vinca rosea L.) with antimitotic and antineoplastic activities. This agent also depolymerizes microtubules and may also interfere with amino acid, cyclic AMP, and glutathione metabolism; calmodulin-dependent Ca(2+)-activated ATPase activity; cellular respiration; and nucleic acid and lipid biosynthesis.