The interactions between mitochondrial and nuclear Mg concentration for the development of radiation-induced apoptosis were tested IN VIVO in Sarcoma-180 in BALB/c mice. The frequency of apoptosis was expressed as a percentage of TUNEL reactivity in the 5 microscopic views under 400 times magnification, and Mg concentration in either mitochondria or nucleus was measured by Particle Induced X-ray Emission (PIXE), on 3, 6, 9, 12 and 24 hours after the 10 or 20 Gy of 60 Co gamma ray radiation, to the mice with or without the 0.01 mMOL MgCl 2 oral administration. There were proximal increases of apoptosis, which peaked on 9 hours after radiation. The Mg concentration of mitochondria strongly correlated with frequency of apoptosis from 3 to 9 hrs after radiation, and that of the nucleus strongly correlated with frequency of apoptosis from 6 to 24 hours after radiation. The oral administration of MgCl 2 did not change those correlations. The two steps are considered: 1st) signaling from mitochondria to nucleus involving Mg on induction of apoptosis; and 2nd) removal of apoptosis involving nuclear Mg .
Origins of radiation-induced attenuation in pure-silica-core and Ge-doped optical fibers under pulsed x-ray irradiation