Influence of physical factors on the growth of insect cells in vitro: I. Effect of osmotic pressure on growth rate of a moth cell line

The influence of osmotic pressure on the growth rate of a cell line (IMC-HZ-1) from a moth, Heliothis zea, was studied. The cells grew at approximately the same rate in media ranging from 290 to 360 mOsm per kg. On either side of these osmolalities the growth rate fell off considerably. The osmotic pressure tolerances of the cells were similar to those reported for other animal cells. Upon transfer to media of higher osmolality, the moth cells effected further increases in the osmolality of the medium. The relationship between the logarithm of the change in osmolality effected per cell and the initial osmolality of the medium was linear.