Effects of radiation on cultured fish cells

A new fibroblastic cell line was established in our laboratory from the caudal fin of the goldfish, C. auratus. The cells, designated CAF, have been subcultured over 80 passages since initiation in August, 1977. A brief description of cell cultivation and colony formation is presented. The plating efficiency obtained was considerably higher than those reported for other fish cell lines. CAF cells were irradiated with 250, 500, 1,000, 2,000, and 3,000 R of x-rays at a dose rate of 80 R/min in air. The survival parameters changed when the number of passages of culture increased. Values for D0, D sub(q), and n obtained from cells irradiated at the 70th passage were calculated to be 650 R, 700 R, and 2.7 respectively. Thus CAF cells would be several times as resistant in general as cultured mammalian cells. The cells irradiated with 1,000 R of x-rays received a second dose from 250 to 2,000 R at intervals of 3, 6, and 24 hr. The cells kept at 260C showed a pronounced recovery from sublethal damage during the intervals between two doses. Magnitude of recovery was larger if the interval was longer under the present experimental conditions. These results may indicate that the recovery observed at an individual level accounts partly for that in vitro. (author)