The effect in vitro of estrone and bradykinin on a nuclear abnormality in a hamster ascites tumor

Abstract

Bradykinin caused a decrease in the number of polynucleated cells only in the presence of estrogens. Bradykinin may influence cell permeability to estrogens, and estrogens may be the active factor instead of bradykinin. However, when bradykinin, estrone, and washed polynucleated cells were incubated in vitro, decrease in polynucleated cell numbers did not occur until after 2 hr. Incubation of bradykinin and estrone for 4 hr before addition of washed polynucleated cells resulted in decreased numbers of polynucleated cells in less than 2 hr. This suggests that bradykinin and estrone form a complex or third product which is the active agent and that the phenomenon may not be explained entirely on the basis of altered cell permeability to estrogens. Effect of agents upon polynucleated tumor cells has been determined by microscopic counts of polynucleated cells before and after incubation. Evidence indicated that reduction in the number of polynucleated cells was the result of cytokinesis occurring around each nucleus in a polynucleated cell. This resulted in an increased number of small tumor cells in the culture. Use of the Coulter particle-size distribution plotter to determine cell size shifts and increased numbers of smaller tumor cells after incubation with bradykinin and estrone offered a simple objective method to replace the laborious and subjective microscopic determination of polynucleated cell numbers.