Prostaglandin F2alpha and insulin stimulate phosphate uptake and (Na+, K+) ATPase activity in resting mouse fibroblast cultures.

The (Na⁺, K⁺)ATPase transport system in resting 3T3 Swiss mouse fibroblasts is rapidly activated by prostaglandin F₂α and insulin, which initiate DNA synthesis in these cells. Prostaglandin F₂α, but not insulin, promotes a rapid increase in P_i uptake which is partially coupled to the Na⁺ pump. This rapid activation of both transport systems occurs by a mechanism which does not require fluctuation of cyclic AMP levels or new protein synthesis. A subsequent protein synthesis-dependent increase in P_i uptake is stimulated by insulin and prostaglandin F₂α. These results suggest that different types of control of membrane transport occur during growth stimulation.