Detection of dysplastic lesions by fluorescence in a model of chronic colitis in rats after local application of 5-aminolevulinic acid and its esterified derivatives.

5-Aminolevulinic acid (ALA) and ALA ester-induced protoporphyrin IX (PPIX) fluorescence are used for photodynamic diagnosis and therapy with promising results. The aim of the present study was to investigate the detection of dysplastic lesions by fluorescence after topical application of ALA and different esterified derivatives in a model of chronic colitis in rats. In female CD rats chronic colitis was induced by oral application of 5% dextrane sulfate sodium.