Unusual product ratios resulting from the gamma-irradiation of cholesterol in liposomes.
Cholesterol in aqueous suspensions of multilamellar vesicles (MLV) was exposed to gamma-irradiation (0.5-10 kGy) at 0-4 degrees C. Cholesterol oxidation products resulting from the irradiation were isolated by dry column extraction followed by preparative thin-layer chromatography (TLC) and were quantitated by on-column gas chromatography (GC). The ratio of 7-ketocholesterol/cholesterol 5,6-epoxides generated by irradiation was less than one, much lower than the ratio of ten commonly produced by autoxidation. Irradiation also produced relatively higher amounts of 7-hydroxycholesterol than did autoxidation. These unique product ratios may be suitable indicators of past exposure to irradiation.
Maerker
G
G
U.S. Department of Agriculture, Eastern Regional Research Center, Philadelphia, Pennsylvania 19118.
Jones
K C
KC
D015060:1,2-Dipalmitoylphosphatidylcholine; D002784:Cholesterol / Q000737:chemistry / Q000528:radiation effects*; D005720:Gamma Rays; D008081:Liposomes; D010084:Oxidation-Reduction; D010710:Phosphates / Q000032:analysis; D010715:Phosphatidylglycerols
D008081:Liposomes; D010710:Phosphates; D010715:Phosphatidylglycerols; D015060:1,2-Dipalmitoylphosphatidylcholine; D002784:Cholesterol; C030345:1,2-dipalmitoylphosphatidylglycerol