title: Uptake and DNA photodamage induced in plant cells in vivo by two cationic porphyrins.
abstract: The in vivo uptake of two cationic porphyrins: mesotetra (4-N-methylpyridyl) porphine (T4MPyP) and its zinc complex (ZnT4MPyP) was determined in Allium cepa meristematic cells. Both photosensitizers (10(-7) M for 4 h) penetrated into the nucleus producing a red fluorescence of chromatin under blue-violet (436 nm) exciting light. The ability of T4MPyP and ZnT4MPyP to induce DNA photodamage was measured by the sister chromatid exchange (SCE) test. 5-Bromo-2'-deoxyuridine-substituted chromosomes treated with both the porphyrins (10(-8)M for 4 h) showed increased frequencies of SCE when they were postirradiated with 436 nm light. A higher genotoxic effect was observed for ZnT4MPyP than the other compound.
authors.affiliation: Departamento de Biolgía, Facultad de Ciencias, Universidad Autónoma de Madrid, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Villanueva
authors.forename: M
authors.initials: M
authors.lastname: Cañete
authors.forename: M J
authors.initials: MJ
authors.lastname: Hazen
mesh_terms: D000490:Allium / Q000187:drug effects / Q000235:genetics*; D002412:Cations / Q000493:pharmacokinetics; D004249:DNA Damage; D008027:Light; D008652:Mesoporphyrins / Q000493:pharmacokinetics / Q000633:toxicity*; D008665:Metalloporphyrins / Q000493:pharmacokinetics / Q000633:toxicity*; D009152:Mutagenicity Tests; D009153:Mutagens; D011166:Porphyrins / Q000493:pharmacokinetics* / Q000633:toxicity*; D012854:Sister Chromatid Exchange / Q000187:drug effects
chemical_list: D002412:Cations; D008652:Mesoporphyrins; D008665:Metalloporphyrins; D009153:Mutagens; D011166:Porphyrins; C021096:tetra(4-N-methylpyridyl)porphine; C060088:zinc tetra(4-N-methylpyridyl)porphine