Insulin effect on the cell cycle: analysis of the kinetics of growth parameters in confluent chick cells.

Abstract

Several techniques, including flow microfluorometry, were utilized to study the effect of [bovine] insulin on the growth of cultured cells. Chick fibroblasts can be stimulated to synthesize DNA and undergo mitosis after insulin addition. The kinetics of the cell movement through the cell cycle and the length of the cycle itself were distinctly different in insulin- and serum-treated cultures. Insulin-treated cells had a shorter G1, an extended S and a much extended G2 residence time compared to cells treated with serum. A model of growth regulation which includes both primary cultures and cell lines is proposed. [Calf thymus DNA and serum were used.].