Photosensitization of isolated mitochondria by hematoporphyrin derivative (Photofrin): effects on bioenergetics.
Isolated rat liver mitochondria were incubated in the presence of 6 micrograms/ml of Photofrin and irradiated at the wavelength of 365 nm. After 45 s irradiation (30 W/m2), coupling defined as stimulation of respiration by externally added adenosine 5'-diphosphate (ADP) is totally lost. In contrast, membrane potential created by addition of succinate or adenosine 5'-triphosphate (ATP) is only slightly affected. Similarly, the ADP/O ratio is not modified after 20 s irradiation. These data suggest that modification of the mitochondrial membrane potential is not a primary event after irradiation.
Salet
C
C
Laboratoire de Biophysique, INSERM U 201 et CNRS URA 481, Muséum National d'Histoire Naturelle, Paris, France.
Moreno
G
G
Atlante
A
A
Passarella
S
S
D000818:Animals; D017324:Hematoporphyrin Derivative; D006415:Hematoporphyrins / Q000494:pharmacology*; D008564:Membrane Potentials / Q000187:drug effects / Q000528:radiation effects; D008930:Mitochondria, Liver / Q000187:drug effects / Q000378:metabolism / Q000528:radiation effects*; D010085:Oxidative Phosphorylation / Q000187:drug effects / Q000528:radiation effects*; D011838:Radiation-Sensitizing Agents / Q000494:pharmacology*; D051381:Rats; D014466:Ultraviolet Rays
D006415:Hematoporphyrins; D011838:Radiation-Sensitizing Agents; D017324:Hematoporphyrin Derivative