Induction of proliferation in dense non-starved 3T3 cells by Ca++ ionophore A23187

Abstract
Summary The proliferogenic effect of the Ca++ ionophore A23187 was tested in dense non-starved 3T3 cells. Whereas continuous exposure during 48 h of the cells to the ionophore at concentrations ≧0.4 μM was cytotoxic, a short exposure for 30 s up to 4 min at 0.2 μM was proliferogenic. It was also found that such short exposures to the ionophore caused a transient increase in the intracellular level of cyclic GMP and a roughly simultaneously appearing decrease in the intracellular level of cyclic AMP.