Lens epithelium and radiation cataract. V. Observations on acid phosphatase and meridional row nuclear fragmentation.

The influence of X-radiation on acid phosphatase activity in differentiating meridional row cells of rat lens epithelia was examined by ultrastructural cytochemistry. X-ray doses of 10-12 Gy (1000-1200 rads) produced clearly observable nuclear and cytoplasmic damage at 13-19 hr postirradiation. In those cells, acid phosphatase reaction product was associated with much of the electron dense material of fragmented nuclei and various parts of the cytoplasm. In addition, many irradiated cells without observable damage were positive for reaction product. The presence of acid phosphatase activity in these otherwise normal-appearing cells is suggestive of more subtle radiation damage than that observed in the more severely damaged cells.