title: Sufficient PpIX production for PDT even with short contact time of topically applied 5-ALA in rabbit tongues.
abstract: Although effectiveness of photodynamic therapy (PDT) after application of 5-aminolevulinic acid ointment to oral mucosal lesions has been reported, a consensus regarding recontact time of ALA applied to a lesion has been unreached. Hence, we determined the contact time of ALA required for protoporphyrin IX (PpIX) production efficient for full-blown PDT reaction. ALA ointment was topically applied to healthy rabbits' tongues for different periods and then washed out. On the surface of the tongue, 10-min contact of ALA maximized the PpIX-derived fluorescence. PpIX yield in a tissue specimen with 10-min contact of ALA reached 73% of that in a tissue specimen with 240-min contact. Histological observation showed that PpIX accumulation predominated in the basal layer, and the PDT effects were confined in the mucosal epithelium regardless of contact time. These results suggest that 5-aminolevulinic-acid-ointment-mediated PDT with short contact of ALA is potentially applicable for treating tongue epithelial lesions.
authors: Department of Oral and Maxillofacial Surgery, Hamamatsu University School of Medicine, 1-20-1 Handayama, Hamamatsu, Shizuoka 431-3192, Japan. oura@hama-med.ac.jp
authors: Takehiro
authors: T
authors: Oura
authors: Hideo
authors: H
authors: Tanaka
authors: Yuji
authors: Y
authors: Morimoto
authors: Kazuma
authors: K
authors: Masumoto
authors: Eiji
authors: E
authors: Kohno
authors: Toru
authors: T
authors: Hirano
authors: Fuminori
authors: F
authors: Katou
authors: Kenji
authors: K
authors: Hashimoto
mesh_terms: D000622:Aminolevulinic Acid / Q000031:analogs & derivatives / Q000494:pharmacology*; D000818:Animals; D004848:Epithelium / Q000187:drug effects* / Q000528:radiation effects; D008297:Male; D023421:Models, Animal; D009061:Mouth Mucosa / Q000187:drug effects* / Q000528:radiation effects; D010778:Photochemotherapy / Q000379:methods*; D017319:Photosensitizing Agents / Q000494:pharmacology*; D011524:Protoporphyrins / Q000096:biosynthesis* / Q000528:radiation effects; D011817:Rabbits; D013997:Time Factors; D014059:Tongue / Q000187:drug effects* / Q000528:radiation effects
chemical_list: D017319:Photosensitizing Agents; D011524:Protoporphyrins; D000622:Aminolevulinic Acid; C028025:protoporphyrin IX