Аннотация:A series of nanosized (20 nm and larger) samples of hydroxyapatite powders synthesized by wet
preparation method and doped with Mn2+ and Pb2+ ions were studied by 94 GHz pulsed electron
paramagnetic resonance (EPR). The results are compared with those obtained in the samples of aorta
walls from male patients with atherosclerosis as well as in bulk hydroxyapatite materials. It is shown
that in contrast to bulk materials Pb ions at least partially replace the Ca(1) site in the hydroxyapatite
structure. The spectral characteristics of the Mn2+ ions revealed in atherosclerotic plaque and synthetic
hydroxyapatite are found to be practically identical. The hypothesis about the important role of
(nano)hydroxyapatite in formation and rupture of atherosclerotic plaques is supported.