[Pharmacologic analysis of the stimulating effect of serotonin on proliferation in cell cultures]

Serotonin (10-7 M) stimulated cell proliferation in the primary cultures of mouse and human embryonic fibroblasts as well as in mouse L-cells and in monkey kidney cells (MA). The stimulatory effect is completely prevented by pretreatment of cultured cells with serotonin antagonists of tipindole, morphine or cyproheptadine type which do not affect cell proliferation. It is therefore assumed that the stimulatory action of serotonin on these cells is realized via specific serotonin receptors.