Dose-dependent volume changes in X-irradiated keratinocytes

Volume changes in X-irradiated epidermal basal keratinocytes in the rat tail were determined as a function of the radiation dose (1-16 krad) four days after irradiation. Changes in keratinocyte volume could be perceived subjectively on histological sections which showed marked variations in the cross-sectional areas of the basal cells exposed to 2.5, 4.0 and 12.0 krad. Using the numerical density data to calculate the absolute keratinocyte volume, no detectable volumetric change was observed after the 1 krad dose. Between 1.0 and 2.0 krad a small volume increment was noted. Between 2.0 and 4.0 krad, the basal keratinocyte volume increased notably reaching values of approximately 700 μ3 compared to 274 μ3 for non-irradiated keratinocytes. After exposure to 8.0, 12.0 and 16.0 krad, progressive volume increments were detected reaching the latter dose volume values of 1000 μ3. The volume modifications found as a function of the radiation dose support the consideration of this parameter as an indicator of radiation doses at least in the range of higher sensitivity (1.0 to 4.0 krad). (U.K.)