Selective gastrointestinal uptake of ALA and its benefits for laserlight induced fluorescence diagnostics (LIFD) and photodynamic therapy (PDT)

被引：2

作者：

Pressmar, J ^{[1
]}

Stern, J ^{[1
]}

Bohm, J ^{[1
]}

Kohl, B ^{[1
]}

Gahlen, J ^{[1
]}

机构：

[1] Univ Heidelberg, Chirurg Klin, D-69120 Heidelberg, Germany

来源：

MEDICAL APPLICATIONS OF LASERS IN DERMATOLOGY, OPHTHALMOLOGY, DENTISTRY, AND ENDOSCOPY, PROCEEDINGS OF | 1997年 / 3192卷

关键词：

photosensibilisation; ALA; PBG; protoporphyrin IX; LIFD; PDT; resorption; gastrointestinal tract; cancer;

D O I：

10.1117/12.297850

中图分类号：

R78 [口腔科学];

学科分类号：

1003 ;

摘要：

LIFD and PDT are based on the selective uptake of photosensitizers (PS) resp. the selective metabolism of their precursors in malignant tissue. Excitation with laserlight results in fluorescence or phototoxic reactions which can be used for the detection or destruction of colorectal carcinoma and dysplasia, General photosensibilisation resulting in an increased photosensitivity of the whole body represents the main side and necessitates avoidance of daylight for days up to weeks. Local application of delta-aminolevulinic acid (ALA) may reduce systemic uptake. Rats with DMH induced colorectal cancer were photosensitized for LIFD by oral, intravenous or local application of ALA. Urine concentrations of ALA and porphobilinogen (PEG) representing systemic photosensibilisation were determined by two-column chromatography. Local colon application of ALA not only increases the quality of LIFD of colorectal cancer, it also provokes three times lower concentrations of PEG in comparison to oral or intravenous administration and reduces in consequence general photosensibilisation.

引用

页码：269 / 273

页数：5