人工紫外线诱导正常皮肤色素斑的初步研究

A preliminary study of pigmentation spot on healthy skin induced by artificial UV light

目的:建立人工紫外线诱导正常皮肤色素斑的模型。方法:采用日光模拟器人工光源,以连续紫外线(波段290～400nm)照射健康受试者上臂内侧皮肤,观察不同照射剂量及照射后不同测量时间局部皮肤黑素测量值的变化。结果:照射后1周,2.0倍最小红斑量(MED)照射剂量组产生黑素的强度高于1.5MED组(P<0.05),与2.5MED组的差异无统计学意义(P>0.05);2.0MED组红斑消退及表面光滑度较2.5MED组轻(P<0.05),与1.5MED组差异无统计学意义(P>0.05)。紫外线照射后1周,各剂量组黑素测量值(L值)均达到高峰,其后随时间延长迅速下降(P<0.05),在第4、5周下降趋势变缓(P>0.05);而红斑测量值(a值)在紫外线照射1周时达到高峰后呈持续递减趋势(P<0.05)。结论:2.0MED照射剂量是紫外线在正常皮肤诱导色素斑的最佳剂量,照射后1～4周是观察色素变化的最佳时机。

Objective： Establishment of pigmentation spot model induced by artificial UV light. Methods： Irradiating on the skin of healthy people by continuous UV （290-400 nm） used artificial UV light and observing the change of melanochrome values at different doses and different times. Results： At the first week after irradiation, the intensity of the pigmentation of 2.0 minimum erythema dose （MED） group was significantly stronger than 1.5 MED group （P〈 0.05）, and had no statistical difference with 2.5 MED group （P〉 0.05）; the degree of the erythema and the smooth of 2.0 MED group was significantly weaker than 2.5MED group （P〈0.05）, and had no statistical difference with 1.5 MED group（P〉0.05）. At the first week after irradiation, L values of all dose groups reached their peaks and rapidly decreased as time prolonged（P〈O.05） and then the trend became slower at the fourth and fifth weeks（P〉0.05）; a values of all dose groups reached their peaks at the first week after irradiation and rapidly decreased as time prolonged（P〈 0.05）. Conclusions： 2.0 MED of UV irradiation may be the best dose for the production of pigmentation. It is the best time to observe the change of pigmentation in the first 4 weeks after irradiation.