title: Comparison of sister-chromatid exchange induced by photoactivated 3-carbethoxypsoralen and 8-methoxypsoralen in human blood lymphocytes.
abstract: The induction of sister-chromatid exchange (SCE) by a photoactivated monofunctional derivative of psoralen, 3-carbethoxypsoralen (3-CPs) was compared with that of the bifunctional compound, 8-methoxypsoralen (8-MOP). Lymphocytes were exposed in vitro to a series of equimolar concentrations of the drugs as well as to increasing doses of long-wave ultraviolet light (UVA) and second-division metaphases examined for SCE. The drugs or UVA per se did not influence the incidence of SCE. However, combination of the drug and UVA exposure resulted in a dose-dependent increase in SCE and such elevation was less pronounced with 3-CPs as compared to 8-MOP. This difference between 3-CPs and 8-MOP could be due to the difference in the types of lesions induced/repaired in DNA.
mesh_terms: D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D004307:Dose-Response Relationship, Radiation; D011564:Furocoumarins / Q000494:pharmacology*; D006801:Humans; D007700:Kinetics; D008214:Lymphocytes / Q000166:cytology / Q000187:drug effects* / Q000528:radiation effects; D008730:Methoxsalen / Q000494:pharmacology*; D012854:Sister Chromatid Exchange / Q000187:drug effects* / Q000528:radiation effects; D013329:Structure-Activity Relationship; D014466:Ultraviolet Rays
chemical_list: D011564:Furocoumarins; C017104:3-carbethoxypsoralen; D008730:Methoxsalen