Na+/K+ atpase and cell growth-III: Enzymatic activity in cultured and egf stimulated HeLa cells

1. 1. The behaviour of Na⁺/K⁺ ATPase during the growth of ectodermal tumoral cells (HeLa) has been investigated. 2. 2. Besides spontaneously growing cells, also samples stimulated with EGF have been tested. 3. 3. The content of -SH groups in the homogenates of both the untreated and the EGF stimulated samples has been tested. 4. 4. Results show a decrease of enzymatic activity during the culture of neoplastic cells and an enhancement of this behaviour in the EGF stimulated cells due to the action of the hormone on -SH groups.