The Stathmokinetic Effect of V incaleukoblastinc on Normal Bone Marrow and Leukemic Cells*

Vincaleukoblastine (VLB) is a compound recently isolated from Vinca rosea L i n n . Chemical studies by Gorman et al. (6) indicated that it belongs to a new class of dimeric alkaloids containing both indole and dihydroindole moieties. VLB possesses a marked leukopenic effect, due to depression of leukopoiesis (4, 10). I t has been found that this alkaloid is active against several animal tumors and is capable of inducing remission in some human neoplastic diseases (5, 7, 10). The mechanism of action of VLB is not known. Johnson et al. (8) suggested that the compound might act as an antimetabolite by interfering in the metabolic pathways of glutamic acid utilization. Palmer et al. (9) have shown that the substance causes a metaphase arrest of cells growing in tissue culture. The present ,~,~,,~ . . . . ~ deals with the studvr of the effects of Vincaleukoblastine on the mitotic activity of normal bone marrow and leukemic cells in the mouse.