An inhibitor of polyamine synthesis arrests cells at an earlier stage of G1 than does calcium deprivation.
Methylglyoxal bis(guanylhydrazone) completely inhibits the induction of thymidine kinase after serum stimulation of quiescent fibroblasts only if added within 3 h after serum, whereas calcium deprivation blocks this induction up to 12 h after serum stimulation. Experiments in which one of these blocks was imposed as the other was released confirmed that cells blocked by methylglyoxal bis(guanylhydrazone) are arrested at an earlier stage in G1 than cells blocked by calcium deprivation.
D000818:Animals; D002118:Calcium / Q000172:deficiency*; D005260:Female; D005347:Fibroblasts / Q000166:cytology / Q000187:drug effects; D006146:Guanidines / Q000494:pharmacology*; D007399:Interphase / Q000187:drug effects*; D008935:Mitoguazone / Q000494:pharmacology*; D011073:Polyamines / Q000096:biosynthesis*; D011247:Pregnancy; D051381:Rats; D013937:Thymidine Kinase / Q000096:biosynthesis; D013997:Time Factors
D006146:Guanidines; D011073:Polyamines; D013937:Thymidine Kinase; D008935:Mitoguazone; D002118:Calcium