title: [Electron microscopic studies of the effect of x-rays and L-3,4-dihydroxyphenylalanine (L-Dopa)--alone and in combination-- on Harding-Passey melanoma cells in monolayer cell culture].
abstract: Monolayer cultures of Harding-Passey melanoma cells in exponential growth phase were exposed to 8 or 16 Gy by X-ray treatment. The 8 Gy treated cells revealed little ultrastructural changes, while the 16 Gy exposed cells showed increased damage as segregates, swollen mitochondria and vacuoles. Sole treatment with L-3,4-dihydroxyphenylalanine (2 x 10(-4) M L-Dopa) resulted in insignificant electronmicroscopically tangible cell alterations. Combined treatment--starting with 8 Gy irradiation followed by a six-day incubation in the presence of 2 x 10(-4) M L-Dopa--revealed more pronounced cell damage with final cell disintegration; the cytoplasm contained an increased number of vacuoles and segregates, a strongly decreased endoplasmic reticulum as well as swollen mitochondria and less pinocytosis vesicles; the cell surface showed less microvilli. Melanin containing organelles increased after the combination treatment. The growth inhibitory and cell destructive influence of L-Dopa on X-ray pretreated melanogenic melanoma cells was explained with the formation of cytotoxic oxidation products of L-Dopa.
authors.affiliation: Klinik für Strahlentherapie, Philipps-Universität Marburg/Lahn.
authors.forename: H
authors.initials: H
authors.lastname: Proske
authors.forename: D O
authors.initials: DO
authors.lastname: Schachtschabel
authors.forename: G
authors.initials: G
authors.lastname: Plamper
authors.forename: N
authors.initials: N
authors.lastname: Paul
authors.forename: R
authors.initials: R
authors.lastname: Pfab
mesh_terms: D000818:Animals; D007980:Levodopa / Q000494:pharmacology*; D008546:Melanoma, Experimental / Q000473:pathology*; D051379:Mice; D008854:Microscopy, Electron; D014407:Tumor Cells, Cultured / Q000187:drug effects* / Q000528:radiation effects* / Q000648:ultrastructure
chemical_list: D007980:Levodopa
vernacular_title: Elektronenmikroskopische Untersuchungen zur Wirkung von Röntgenstrahlen und L-3,4-Dihydroxyphenylalanin (L-Dopa)--allein und inKombination--auf Harding-Passey-Melanomzellen in Monolayerzellkultur.