Fig. 5

TEM examination of the hippocampus after radiation injury. a and d show the control group. b and e show the 15 Gy group, and c and f show the 25 Gy group. After radiation injury, the nuclear chromatin aggregates, the nuclear membrane remains intact, the cytoplasmic electron density increases, mitochondria swell, the crista breaks or even disappears, and the cell volume shrinks. These changes were more severe in the 25 Gy group than in the 15 Gy group and were more pronounced at day 4 (b and c) than at week 8 (e and f). ER, endoplasmic reticulum, N, nucleus, Mi, mitochondrion. Red arrows indicate apoptotic neurons. Note. a-c acquired from JEM-1400PLUS, JEOL, d-f acquired from H-600IV, Hitachi