ABSTRACT
The effect of the physiologically active substances (histamine, serotonin) and their antagonists (bicarfene, cyproheptadine and preparation 407) on the growth of Chinese hamster fibroblasts in vitro has been studied. The cell survival evaluated from the number of colonies grown by the 7th day of cultivation served as criterion for the action of the substances under study. Determination of amines in fibroblast extracts was made by spectrofluorometry. It has been discovered that Chinese hamster fibroblasts are susceptible to a number of pharmacological preparations, antagonists of serotonin and histamine, and that histamine abolishes the inhibitory action of the respective antagonist on the colony growth. Biochemical analysis has shown that these fibroblasts contain tryptamine and serotonin and, tentatively, histamine. It is assumed that these endogenous physiologically active substances participate in the fibroblast growth control.