(Mg2+ + Ca2+)-ATPase activity in plasma membrane enriched preparations of human skin fibroblasts: decreased activity in fibroblasts derived from cystic fibrosis patients

Clin Chim Acta. 1980 Jan 31;100(3):245-52. doi: 10.1016/0009-8981(80)90273-9.


Plasma membrane enriched preparations obtained from cultured human skin fibroblasts by differential centrifugation and sucrose density centrifugation techniques were found to contain a Mg2+-dependent Ca2+-stimulated ATPase activity. The specific activity of the (Mg2+ + Ca2+)-ATPase present was 4-5-fold higher than that present in crude membrane preparations and 80-100-fold higher than that present in homogenates. The (Mg2+ + Ca2+)-ATPase activity of both crude and plasma membrane enriched preparations of cultured fibroblasts from cystic fibrosis patients was significantly reduced compared to that activity observed in age-matched controls. This study corroborates our previous observations made in crude homogenate preparations of fibroblasts and indicates another cell type where (Mg2+ + Ca2+)-ATPase activity may be altered in cystic fibrosis.

MeSH terms

  • Calcium-Transporting ATPases / metabolism*
  • Cell Membrane / enzymology
  • Child
  • Cystic Fibrosis / enzymology*
  • Fibroblasts / enzymology
  • Humans
  • Magnesium
  • Skin / cytology


  • Calcium-Transporting ATPases
  • Magnesium