... enhance-ment of cellular proliferation, the increase in the hydrogenperoxide concentration and the GPX inhibition caused by the addition of the insulin mediator. Hydrogen peroxide, atnoncytotoxic concentrations, ... (H2O2) concentration in the medium,concomitantly with the disappearance of the GPX activity in the same conditions. The presence of insulin or anyone of both products, during 48 h, induces cell ... significant increase in concentration of the peroxidase inhibitor by the action of insulin, during 48 h, in thyroid primary cultures with 0.1% fetal bovine serum,totally depleted of the hormone, 48...