[Protein metabolism and sensitivity to tetrodotoxin of cardiomyoblasts cultured in vitro. Influence of insulin (author's transl)].
1. Insulin prevents the decrease in sensitivity to tetrodotoxin in populations of embryonic cardiomyoblasts cultured in vitro. This effect of insulin remains when the hormone is added to the culture medium up to 16 hours after the beginning of the culture. 2. Amino-acid deprivation results in an acceleration of the loss of sensitivity to tetrodotoxin in cultured cardiomyoblasts. Addition of cycloheximide, an inhibitor of protein synthesis, has the same effect. These results suggest that the sensitivity to tetrodotoxin of the cardiac cells depends on aspects of protein metabolism which can be controlled by insulin. 3. Return of the cell population to a culture medium containing amino acids and serum or insulin after 7 hours of culture in an amino acid free medium induces a striking increase in the percentage of cardiac cells sensitive to tetrodotoxin. This sensitivity to the inhibitor of the fast sodium carrying mechanism appears to be an element of the pleiotypic response of the cells in culture to serum or to insulin.
D000596:Amino Acids / Q000378:metabolism; D000818:Animals; D002478:Cells, Cultured; D002642:Chick Embryo; D003513:Cycloheximide / Q000494:pharmacology; D007328:Insulin / Q000494:pharmacology*; D007473:Ion Channels / Q000187:drug effects / Q000378:metabolism; D009206:Myocardium / Q000166:cytology*; D011506:Proteins / Q000378:metabolism*; D012964:Sodium / Q000378:metabolism; D013779:Tetrodotoxin / Q000494:pharmacology*
D000596:Amino Acids; D007328:Insulin; D007473:Ion Channels; D011506:Proteins; D013779:Tetrodotoxin; D003513:Cycloheximide; D012964:Sodium
Métabolisme protéique et sensibilité à la tétrodotoxine des cardiomyoblastes cultivés in vitro. Influence de l'insuline.