Characteristics of lead adaptation in a rat kidney cell line. II. Effect on DNA synthesis, protein synthesis, and gene expression.
The effects of adaptation of normal rat kidney cells (NRK 52-E) to growth in 5 or 10 microM lead nitrate on the rates of DNA synthesis and on the rate and pattern of protein synthesis was studied. The rate of [3H]thymidine incorporation into DNA was increased in normal cells, but remained unchanged in one lead-adapted cell line (only 5 microM NRK studied). Increased rates of [3H]leucine incorporation into nonadapted NRK cells were found only at times up to 3 h; in contrast, the lead-adapted cells showed such increases only at longer times. The most pronounced differences between normal and lead-adapted cells were found with lead concentrations of 10 or 50 microM lead nitrate. Lead-adapted control cells incorporated 170% of the [3H]leucine taken up by nonadapted cells. In both adapted and nonadapted cells the pattern of synthesis of specific proteins showed varied and dose-dependent differences between the three cell sublines examined. The changed sensitivity of both DNA and protein synthesis following lead exposure appears to be a potent parameter in the development of resistance, perhaps through the development of specific lead-binding proteins.
Hitzfeld
B
B
Institute of Genetics and Toxicology, Kernforschungszentrum Karlsruhe, Germany.
Taylor
D M
DM
D000818:Animals; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D004261:DNA Replication / Q000187:drug effects*; D015180:Electrophoresis, Gel, Two-Dimensional; D015870:Gene Expression / Q000187:drug effects*; D007668:Kidney / Q000187:drug effects / Q000378:metabolism; D007700:Kinetics; D007854:Lead / Q000494:pharmacology*; D008715:Methionine / Q000378:metabolism; D014176:Protein Biosynthesis; D011506:Proteins / Q000302:isolation & purification; D051381:Rats
D011506:Proteins; D007854:Lead; D008715:Methionine