EFFECTS OF ACIVICIN AND DIPYRIDAMOLE ON HEPATOMA 3924A CELLS

  • 1 January 1983
    • journal article
    • research article
    • Vol. 43  (4) , 1616-1619
Abstract
Dipyridamole inhibited the incorporation of cytidine, thymidine, uridine, and guanosine in rat hepatoma 3924A cells with 50% inhibitory concentrations of 0.2 to 0.5 .mu.M. For deoxycytidine, the 50% inhibitory concentration was about 100 times higher (23.8 .mu.M). Addition of a combination of cytidine, deoxycytidine and guanosine, at an optimal concentration of 80 .mu.M each, protected the hepatoma cells from the growth-inhibitory action of the antiglutamine drug, acivicin. The protection provided by the nucleosides was blocked by dipyridamole (6 .mu.M), but not by nitrobenzythioinosine (30 .mu.M). The effect on cell survival of graded concentrations of 0.25-1.75 .mu.M acivicin plus dipyridamole (5 .mu.M) and 80 .mu.M concentrations each of cytidine, deoxycytidine, and guanosine was investigated. At an acivicin concentration of 1.75 .mu.M, survivals in the different groups were: acivicin alone, 1%; acivicin plus dipyridamole, 1%; acivicin plus nucleosides, 78%; and acivicin plus nucleosides plus dipyridamole, 3%. Acivicin and dipyridamole were cytotoxic for hepatoma 3924A cells with 50% inhibitory concentrations of 0.5 and 20.3 .mu.M, respectively, as measured by clonogenic assay.