Metabolic evaluation of sexual dimorphism. V. Action of testosterone on the phosphofructokinase of mice submaxillary gland cells in vitro.

1) The kinetics of phosphofructokinase and growth rate of submaxillary gland cells of C3H mice of both sexes in presence and in absence of testosterone have been studied. 2) Both enzymes show sigmoidal kinetics, with Hill's coefficient higher for the females. 3) The maximal activity is remarkably more elevated for the males. 4) The testosterone modifies the growth rate and the kinetic properties of the phosphofructokinase and these modifications depend on the sex.