摘要目的 探讨卡泊三醇预处理对外用氨基酮戊酸(ALA)后裸鼠正常上皮中原卟啉Ⅸ(PpIX)含量的影响.方法 将36只BALB/C裸鼠随机等分为ALA组和卡泊三醇+ALA组,卡泊三醇+ ALA组预先外用卡泊三醇软膏3d,3d后两组均外敷ALA,此后2～7h内每小时每组处死3只小鼠,取背部实验区皮肤组织,荧光分光光度计测定裸鼠正常上皮组织中PpIX含量,倒置荧光相差显微镜观察上皮组织冰冻切片中PpIX荧光强度及分布.结果 两组裸鼠外用ALA后2～7h内皮肤组织PpIX含量随时间逐渐增加,相关性分析显示,ALA组PpIX含量与时间无显著相关性(r=0.451,P=0.369,),但卡泊三醇+ALA组PpIX含量与时间呈强相关(r=0.913,P=0.011).ALA组PpIX含量在第5小时达到高峰[(461.24±43.45) ng/g组织],卡泊三醇+ALA组在第6小时达高峰[(668.88±42.46) ng/g组织],且在2、3、4、5、6、7h时卡泊三醇+ALA组PpIX含量明显高于单纯ALA组,差异均有统计学意义(P＜ 0.05或0.01).冰冻切片显示,PpIX弥漫性分布于裸鼠表皮层和真皮层,卡泊三醇+ ALA组荧光强度在第5～7小时高于ALA组.结论 卡泊三醇预处理可以提高ALA作用后裸鼠正常上皮中表皮及真皮层内PpIX含量,为临床上卡泊三醇作为局部ALA-PDT的增效剂提供了理论依据.

abstractsObjective To evaluate the effect of pretreatment with calcipotriol on protoporphyrin Ⅸ (PpIX) content in the normal epithelium of nude mice after topical application of aminolevulinic acid (ALA).Methods A total of 36 BALB/C nude mice were randomly and equally divided into 2 groups:calcipotriol + ALA group topically pretreated with calcipotriol ointment for 3 days followed by topical application of ALA,and ALA group topically treated with ALA alone.At 2,3,4,5,6 and 7 hours after ALA application,3 mice in each group were sacrificed separately,and skin tissues were obtained from the experimental region in the back of mice.A fluorospectrophotometer was used to detect the PpIX content in the normal epithelial tissue of the nude mice,and an inverted fluorescence phase-contrast microscope to observe the fluorescence intensity and distribution of PpIX in the frozen sections of epithelial tissues.Results During 2-8 hours after topical application of ALA,the content of PpIX in the skin tissues of nude mice in the two groups gradually increased over time.Correlation analysis revealed no correlations between the PpIX content in the ALA group and the treatment duration (r =0.451,P =0.369),while the PpIX content in the calcipotriol + ALA group was strongly correlated with the treatment duration (r =0.913,P =0.011).The PpIX content in the ALA group reached a peak at 5 hours [(461.24 ± 43.45) ng/g tissues],while the PpIX content in the calcipotriol + ALA group peaked at 6 hours [(668.88 ± 42.46) ng/g tissues].At 2,3,4,5,6 and 7 hours after ALA application,the PpIX content was significantly higher in the calcipotriol + ALA group than in the ALA group (P ＜ 0.05 or 0.01).Frozen-section examination showed that PpIX was diffusely distributed in the epidermis and dermis of the nude mice,and the fluorescence intensity of PpIX was higher in the calcipotriol + ALA group than in the ALA group at 5,6 and 7 hours after ALA application.Conclusion Pretreatment with calcipotriol can increase the content of PpIX in the normal epidermis and dermis of nude mice after topical application of ALA,which provides a theoretical basis for the clinical application of calcipotriol as a local synergist of ALA-PDT.