|Budget Amount *help
¥2,400,000 (Direct Cost : ¥2,400,000)
Fiscal Year 1997 : ¥1,200,000 (Direct Cost : ¥1,200,000)
Fiscal Year 1996 : ¥1,200,000 (Direct Cost : ¥1,200,000)
UV radiation from three wavelengths, i.e.UVA (340-400 nm), UVB (290-320 nm) and UVC (200-290 nm), were shown to induce apoptosis in OCP13 cells by DNA ladder formation in cells detached from the plastic dish after irradiation. Morphological changes of the irradiated cells occurred in 4 hours after each wavelength UV.
However, the following phenomena only occurred with UVB or UVC irradiation, but not with UVA irradiation. 1), UV-induced detachment of cells from substratum was inhibited with cycloheximide treatment. 2), the characteristic features of the morphological changes after UV irradiation, such as distorted nuclear shape and rearrangement of cells occurred. 3), the morphological changes described above could be evaded by photorepair. 4), the cells attached on both plastic dish and coverslip shows similar morphological changes after UV irradiation. 5), caspase 3, which is activated in apoptosis process in mammalian cells, was also highly activated after UV irradiation.
These results indicate a different pathway between long (UVA) and short (UVB and UVC) wavelength UV-induced apoptosis. UVA-induced apoptosis would not be triggered through CPDs or requires caspase 3 activity as UVB and UVC-induced apoptosis.