Membrane protein detachment and mitogenic stimulation induced by alkaline pH.

The stimulatory effects on DNA-synthesis by a short alkaline treatment in low serum concentration on quiescent 3T3-cells in sparse cultures was investigated. It was found that a short alkaline treatment performed at 4 degrees C stimulated quiescent cell to initiate DNA-synthesis to the same extent as a short alkaline treatment at 37 degree C. Furthermore, an alkaline treatment caused a detachment of membrane bound proteins. The quantity of these proteins that were detached during the alkaline treatment, was closely correlated to the stimulatory effects on DNA-synthesis.