Activation of Lipid Metabolism of Nuclei and Chromatin in Thymocytes of
Rats Subjected to Chronic Low Dose Intensity gamma-Irradiation
T. P. Kulagina1
1Institute of Cell Biophysics, Russian Academy of Sciences,
Pushchino, Moscow Region, 142292 Russia; fax: (7-0967) 79-0509; E-mail:
admin@mars.ibioc.serpukhov.su
Submitted April 9, 1997; revision submitted May 2, 1997.
Contents and radioactivity (as incorporation of
[2-14C]acetate) of thymocyte nuclear and chromatin lipids
were investigated in rats subjected to chronic gamma-irradiation
in a dose 10 Gy at the intensity of 12.9 cGy/day. The incorporation of
label into total fraction of lipids of nuclei and chromatin and into
total phospholipid fraction of thymocyte nuclei increased. However, in
the whole cells differences in radioactivity of these fractions were
not found. The amount of fatty acids in thymocytes from irradiated rats
was decreased but synthesis of fatty acids was activated. The amount of
fatty acids in nuclei and chromatin remained unchanged compared with
control, whereas radioactivity was significantly higher than in the
whole cells. In irradiated thymocytes the amounts of phosphatidylserine
in nuclei and phosphatidylserine and phosphatidylinositol in chromatin
were increased. The incorporation of [2-14C]acetate into
proteins increased in thymocytes of irradiated rats. The role of lipid
metabolism in genome functioning is discussed.
KEY WORDS: lipids, rat thymocytes, nuclei, chromatin,
gamma-irradiation.