Complete elimination of mitosis and DNA synthesis in the lens of the hypophysectomized frog: effects on cell migration and fiber growth.

Three weeks after hypophysectomy mitosis and DNA synthesis are absent in the lens of the leopard frog (Rana iiens). By labeling germinative zone cells in their last DNA synthetic period we were able to follow them in the absence of further proliferation. By this means it has been demonstrated that migration of epithelial cells to the equator of the lens is stopped. Based on indirect measurements it seems that lens fiber formation also ceases. A correlation coefficient of 0.86 was computed between average labeling index and average distance migrated. In hypophysectomized animals the correlation coefficient between time and migration was 0.02 while in intact animals it is 0.87.