Pharmacokinetics of 5-aminolevulinic-acid-induced porphyrins in tumour-bearing mice.
J Photochem Photobiol B
; 34(1): 13-9, 1996 Jun.
Article
em En
| MEDLINE
| ID: mdl-8765659
ABSTRACT
Photodynamic therapy and photodynamic diagnosis help to support efficient treatment of superficial and early-stage cancer. During the last few years, 5-aminolevulinic acid (5-ALA), a precursor of haemoglobin in the haem biosynthetic pathway, was used to stimulate endogenous porphyrin production. In the following the time dependence of 5-ALA-induced porphyrin concentration will be investigated on several tissues in an in-vivo tumour model. 5-ALA was administered intravenously at a concentration of 50 mg-1 body weight. According to a certain time schedule the animals were sacrificed and 12 different organs as well as the tumour were removed. During excitation with the violet light of a Kr+ laser, porphyrin fluorescence spectra in the range 550-750 nm could be detected on the tissue samples. The intensity of the emission spectra at lambda = 635 +/- 2 nm was taken as a measure of the porphyrin concentration. All tissues showed porphyrin fluorescence. Brightest fluorescence was found on the tumour. A maximum contrast of the fluorescence intensity between the tumour and the non-malignant organs of up to 30 was observed at 4-6 h post-injection. The kinetics of the porphyrin concentration depend on the organ. Simple mathematical models will be derived and discussed.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Porfirinas
/
Ácido Aminolevulínico
/
Neoplasias
Tipo de estudo:
Prognostic_studies
Limite:
Animals
/
Humans
Idioma:
En
Revista:
J Photochem Photobiol B
Assunto da revista:
BIOLOGIA
Ano de publicação:
1996
Tipo de documento:
Article
País de afiliação:
Alemanha