IMPACT OF SERUM CONCENTRATION OF THE MEDIUM AND FASTING ON THE IMPRINTABILITY OF THE INSULIN-RECEPTORS OF CHANG LIVER-CELLS

When the cells of the Chang cell line came into interaction with a hor mone (insulin) an imprinting-like phenomenon took place. The binding c apacity of the receptors strengthened and this feature was transmitted to the descendant generations. The quality of the nutrient medium inf luenced the development of imprinting, when the cells were maintained in a medium containing 2% serum it was more difficult to evoke imprint ing than in case the cells were kept in a medium containing 10% serum. If the cells were cultured kept in Tyrode (physiological) solution fo r 24 hours the possibility to evoke imprinting was lost. Difference co uld be observed between the behaviour of receptors in nuclear membrane and that of receptors in the plasma membrane; i.e. changes were more dynamic in the plasma membrane.