title: Effects of extracellular Ca2+ and Mg2+ on nucleic acids and proteins syntheses by tumor and normal liver cells.
abstract: The effects of increasing extracellular concentrations of Ca2+ and Mg2+ on the uptake of 14C-thymidine, 3H-uridine and 14C-leucine by Novikoff hepatoma and normal liver cells have been studied. Increasing concentrations of Ca2+ stimulate all the three incorporations while Mg2+ exhibits an inhibitory effect. Liver cells presented a higher cation permeation induced by the extracellular concentration than hepatoma cells which also seems to explain the quantitative differences observed in the studied syntheses. The importance of the extracellular cation-cell membrane interaction in these effects is discussed.
mesh_terms: D000818:Animals; D002118:Calcium / Q000494:pharmacology*; D002463:Cell Membrane Permeability; D004247:DNA / Q000096:biosynthesis; D066298:In Vitro Techniques; D007930:Leucine / Q000378:metabolism; D008099:Liver / Q000378:metabolism*; D008113:Liver Neoplasms / Q000378:metabolism*; D008114:Liver Neoplasms, Experimental / Q000378:metabolism*; D008274:Magnesium / Q000494:pharmacology*; D014176:Protein Biosynthesis; D012313:RNA / Q000096:biosynthesis; D051381:Rats; D013936:Thymidine / Q000378:metabolism; D014529:Uridine / Q000378:metabolism
chemical_list: D012313:RNA; D004247:DNA; D007930:Leucine; D008274:Magnesium; D002118:Calcium; D013936:Thymidine; D014529:Uridine