C. Feurgard et al., EFFECTS OF IONIZING-RADIATION (NEUTRONS GAMMA-RAYS) ON PLASMA-LIPIDS AND LIPOPROTEINS IN RATS, Radiation research, 150(1), 1998, pp. 43-51
Citations number
34
Categorie Soggetti
Biology Miscellaneous","Radiology,Nuclear Medicine & Medical Imaging
Male Wistar rats weighing 250 g were exposed to 4 Gy of neutrons/gamma
radiation (3.33 Gy of neutrons and 0.66 Gy of gamma rays). After whol
e-body irradiation, plasma cholesterol and phospholipid levels increas
ed up to 62 and 37%, respectively, at day 4 and then returned to contr
ol values 12 days after irradiation. Plasma triglyceride concentration
s decreased concomitantly with decreased food intake after irradiation
but remained higher than in pair-fed control rats. Plasma lipoprotein
s were separated by ultracentrifugation on a density gradient (1.006-1
.210 g/ml). Four days after irradiation, most of the cholesterol (62%
compared to 31% in controls, P < 0.001) is transported by apolipoprote
in E-rich high-density lipoproteins. At the same time, plasma levels o
f apolipoproteins B and E were increased by 28 and 65%, respectively,
while those of apolipoproteins AI and AIV were reduced by 21 and 59%,
respectively. While in the liver of irradiated rats the apolipoprotein
B/E receptor number was not modified, the hydroxymethylglutaryl coenz
yme A reductase activity was fivefold higher than in control pair-fed
rats. Four days after irradiation, the susceptibility of lipoproteins
to peroxidation, as measured by the formation of conjugated dienes in
the presence of CU2+, was markedly increased while plasma vitamin E le
vels were decreased, demonstrating that irradiation reduces antioxidan
t stores markedly. These results suggest that such modified lipoprotei
ns could be involved in radiation-induced vascular damage. (C) 1998 by
Radiation Research Society.