[The characteristics of the radiation-initiated peroxidation of the phosphatidylcholine making up liposomes containing phospholipids which are susceptible to free-radical fragmentation].
The regularities of accumulation of conjugated dienes and thiobarbituric acid (TBA)-reactive substances under gamma-irradiation of liposomes from rat liver phosphatidylcholine (PC) and its mixtures with the resistant to lipid peroxidation saturated phospholipids and bovine brain sphingomyelin (SM) were studied. It was established that the incorporation of negatively charged dipalmitoylphosphatidylglycerol (DPPG) and dipalmitoylphosphatidylethanol (DPPET) into lipid bilayer resulted in the increase of primary and secondary products of LPO, whereas neutral dipalmitoylphosphatidylcholine (DPPC) and SM involving in the phospholipid mixtures inhibited the peroxidation of PC. For anionic phospholipids, DPPG had more profound activating action on LPO, amongst the neutral phospholipids SM was more potent inhibitor of the reaction. Unlike DPPET and DPPC, DPPG and SM were subjected to free radical fragmentation on gamma-radiation. It is suggested that the intermediates and products of free radical fragmentation may modulate the progress of LPO.
Davydov
V Iu
VIu
Institute of Bioorganic Chemistry, National Academy of Sciences, Minsk, Belarus.
Kisel'
M A
MA
Shadyro
O I
OI
Iurkova
I L
IL
D000255:Adenosine Triphosphate / Q000494:pharmacology; D000818:Animals; D001921:Brain / Q000187:drug effects / Q000378:metabolism / Q000528:radiation effects; D002417:Cattle; D005296:Ferrous Compounds / Q000494:pharmacology; D005609:Free Radicals / Q000378:metabolism / Q000528:radiation effects; D005720:Gamma Rays; D008051:Lipid Bilayers / Q000378:metabolism / Q000528:radiation effects; D015227:Lipid Peroxidation / Q000187:drug effects / Q000528:radiation effects*; D008081:Liposomes / Q000378:metabolism / Q000528:radiation effects*; D008099:Liver / Q000187:drug effects / Q000378:metabolism / Q000528:radiation effects; D008297:Male; D010713:Phosphatidylcholines / Q000378:metabolism / Q000528:radiation effects*; D010743:Phospholipids / Q000378:metabolism / Q000528:radiation effects*; D051381:Rats; D017382:Reactive Oxygen Species; D013109:Sphingomyelins / Q000378:metabolism / Q000528:radiation effects
D005296:Ferrous Compounds; D005609:Free Radicals; D008051:Lipid Bilayers; D008081:Liposomes; D010713:Phosphatidylcholines; D010743:Phospholipids; D017382:Reactive Oxygen Species; D013109:Sphingomyelins; C020748:ferrous sulfate; D000255:Adenosine Triphosphate