[Combined action of juvenile hormone and ecdysterone on Drosophila cell lines in vitro].

The action of juvenile hormone used alone or combined with ecdysterone was studied on in vitro diploid cell lines or clones of Drosophila. The solubility of juvenile hormone in the culture medium was estimated to be 10(-8) M. At this concentration, which can be considered as physiological, juvenile hormone slows down the process of ecdysone-induced morphological modifications of the cells. This action is reversible. Concentrations of about 10(-4) M inhibit all reactions to ecdysterone and bring about the death of the cells. This effect is probably non-specific.