Malik Z, Kostenich G, Roitman L, Ehrenberg B, Orenstein A
Life Sciences Department, Bar Ilan University, Ramat Gan, Israel.
J Photochem Photobiol B. 1995 Jun;28(3):213-8. doi: 10.1016/1011-1344(95)07117-k.
Topical 5-aminolevulinic acid (ALA) application in three different creams was carried out on mice bearing subcutaneously transplanted C26 colon carcinoma. The creams contained (a) 20% ALA alone, (b) ALA with 2% dimethylsulphoxide (DMSO) and (c) ALA, DMSO and 2% edetic acid disodium salt (EDTA). Protoporphyrin IX (PP) production in the tumour and in the skin overlying the tumour was studied by two methods: laser-induced fluorescence (LIF) and chemical extraction. The kinetics of PP production in the skin and in the tumour, as studied by the LIF method, was similar for all three cream preparations. The PP fluorescence intensity in the tissues reached its maximum 4-6 h after application of the creams. Quantitative analysis showed that the PP concentration after treatment was more pronounced in the skin than in the tumour. The efficiency of porphyrin production in the skin by the creams used was in the following order: ALA-DMSO-EDTA > ALA-DMSO > ALA. In the tumour the enhancing effect of DMSO and EDTA on PP accumulation induced by ALA was observed mainly in the upper 2 mm section. However, the concentration of PP in the tumour was found to be approximately the same for ALA-DMSO and ALA-DMSO-EDTA cream combinations. The possible mechanisms of the effect of DMSO and EDTA are discussed.
对皮下移植了C26结肠癌的小鼠，在三种不同乳膏中局部应用5-氨基乙酰丙酸（ALA）。这些乳膏分别含有：（a）仅20%的ALA，（b）ALA与2%二甲基亚砜（DMSO），（c）ALA、DMSO和2%乙二胺四乙酸二钠盐（EDTA）。采用激光诱导荧光（LIF）和化学萃取两种方法，研究肿瘤及肿瘤上方皮肤中卟啉原IX（PP）的生成情况。通过LIF方法研究发现，对于所有三种乳膏制剂，皮肤和肿瘤中PP生成的动力学情况相似。乳膏涂抹后4 - 6小时，组织中的PP荧光强度达到最大值。定量分析表明，处理后皮肤中的PP浓度比肿瘤中的更显著。所用乳膏在皮肤中产生卟啉的效率顺序如下：ALA - DMSO - EDTA > ALA - DMSO > ALA。在肿瘤中，DMSO和EDTA对ALA诱导的PP积累的增强作用主要在上方2毫米的切片中观察到。然而，发现ALA - DMSO和ALA - DMSO - EDTA乳膏组合在肿瘤中的PP浓度大致相同。文中讨论了DMSO和EDTA作用的可能机制。
