1P329 Participation of reactive oxygen species in Ultravioret B-induced inflarnmation in hairlessmice

Ultraviolet (UV) irradiation causes rubor, edema, fever and erythema in the skin. UV-irradiation has been shown to produce reactive oxygen species (ROS) in the skin. However, the participation of ROS in the progress of UV-induced inflammation remains unknown. Therefore, we studied the participation of ROS in UVB - induced inflammation using an UVB irradiated hairlessmouse model. Male hairlessmice (7weeks old) were used. Dorsal skin (2cmx2cm) was exposed to UVB lamp (wave length 275-305nm;1.5kJ/m2) and observed for five days after irradiation. SOD (15min before, i. v.), catalase (30min before, i. v. ), ascorbic. acid (before 5min, i. v. ) or indomethacin (30min before, p. o. ) were administrated before irradiation. After irradiation, mice showed rubor (3-6 hrs), edema (24 hrs) and erythema (4-5 days). Rubor at 6 hrs after irradiation was attenuated by indomethacin. Erythema at 5 days after irradiation was attenuated by catalase, but enhanced by SOD. In conclusion, our results suggested that the rubor is related to the production of prostaglandins at 6 hrs after irradiation, and that the erythema is related to hydrogen peroxide and/or downstream ROS at 5 days after irradiation.