Effect of imposed serum deprivation on growth of the mouse 3T3 cell. Dissociation from changes in potassium ion transport as measured from [⁸⁶Rb]rubidium ion uptake

Decreased serum concentrations that substantially alter the growth of normal 3T3 cells alter neither the active and non-active components of unidirectional ⁸⁶Rb⁺ influx nor the intracellular K⁺ content when compared with cells in exponential growth. Thus the changes in K⁺ transport (measured with ⁸⁶Rb⁺ as an analogue for K⁺ movements) that occur in density-dependent growth inhibition of the mouse 3T3 cell are not mimicked by serum deprivation of the cells before density inhibition.