ABSTRACT
Single cell suspensions of Chinese hamster lung cells were treated with hematoporphyrin derivative (HPD) and were exposed under aerobic conditions to visible light alone, X rays alone or light and X rays concurrently. Cytotoxicity was assayed using the colony formation ability of cells as the end point. The drug toxicity, phototoxicity, radiosensitization and photoradiosensitization of HPD were examined for a drug concentration of 1 microgram/ml and incubation time of 24 h. In these experiments, the X-ray dose was 3 Gy and the energy fluence of visible light was 0.35 kJ/m2, and both irradiations lasted for 10 min. A significant enhancement in cytotoxicity was observed when the HPD-treated cells were irradiated concurrently with light and X rays. However, no significant enhancement was observed when visible-light and X irradiations were performed sequentially with a 15-min waiting time between the two irradiations.
Subject(s)
Cell Survival/drug effects , Hematoporphyrin Derivative/pharmacology , Photochemotherapy , Animals , Cell Line , Cell Survival/radiation effects , Cricetinae , Cricetulus , Light , Lung/drug effects , Lung/radiation effects , Suspensions , X-RaysABSTRACT
The extraction, separation and quantification of free acid erythrocyte porphyrins are described. The porphyrins are extracted from whole blood using 3:1 ethyl acetate/acetic acid (v/v) and separated using the reversed-phase mode of high performance liquid chromatography (RPLC). The compounds are detected on-line spectrofluorometrically using an excitation wavelength of 404 nm and an emission cut-off filter of 550 nm. Excellent resolution of the porphyrin free acids is achieved in less than 6 min. The analytical recoveries for protoporphyrin IX and zinc protoporphyrin IX were greater than 90% with relative standard deviations for day-to-day analysis under 6%.