title: Pleiotypic response of rat heart cells in culture to serum stimulation.
abstract: The pleiotypic effects of medium replacement were studied in rat heart cell cultures. After each medium change alpha-aminoisobutyric acid and glucose transport are increased, RNA and protein syntheses are activated. DNA synthesis did not begin before 12 hours and was followed by a wave of mitoses. This sequence of events suggests that the stimulated cells were in early G 1 phase. DNA synthesis, following the shift to a fresh medium, is linearly related to the amount of serum used as is protein synthesis. However when serum concentrations higher than 20 percent were used no increased protein synthesis could be observed suggesting the existence of another limiting factor, which was probably the isoleucine content of the medium. The serum stimulating factor is heat stable, dialysable and was found in both human and fetal calf sera.
mesh_terms: D000621:Aminoisobutyric Acids / Q000378:metabolism; D000818:Animals; D001693:Biological Transport, Active; D001769:Blood; D002478:Cells, Cultured; D003470:Culture Media; D004261:DNA Replication; D005947:Glucose / Q000378:metabolism; D006321:Heart / Q000502:physiology*; D007700:Kinetics; D009124:Muscle Proteins / Q000378:metabolism; D009206:Myocardium / Q000378:metabolism*; D014176:Protein Biosynthesis; D051381:Rats; D014158:Transcription, Genetic
chemical_list: D000621:Aminoisobutyric Acids; D003470:Culture Media; D009124:Muscle Proteins; D005947:Glucose