Inhibition of cell division in rat lenses by prostaglandin E1

Prostaglandin E1 (PGE1) suppresses mitotic activity in the epithelial cells of rat lenses maintained in organ culture. At a concentration of 5 x 10(-5)M, PGE1 caused gradual inhibition of mitosis which was first evident after six hours of incubation and was maximum at 50 per cent of control values after 16 and 24 hours in culture. During this period prostaglandin-treated lenses showed no change in the number of cells labeled with H3-thymidine, but the amount of radioactive precursor incorporated per cell was reduced by almost half. At a higher concentration (1 x 10(-4)M) PGE1 evoked a transient mitotic inhibition within the first few hours of culture, but caused cell damage after 24 hours of incubation; a lower dose (1 x 10(-5M) had no influence on mitotic activity.