Fig. 7.
SS (Dahl salt-sensitive/Mcwi) rat hearts have decreased mast cell infiltration compared with SS-3BN (substitution of rat chromosome 3 from the resistant Brown Norway rat strain onto the SS background) rat hearts at 10–12 wk following 24 Gy × 1 or 9 Gy × 5 localized heart radiation. Mast cells were stained using toluidine blue in left ventricle sections from female rats 10 wk after localized cardiac treatment with 24 Gy × 1 (A–E) or 12 wk after 9 Gy × 5 (F–J). There was no difference between the mast cell infiltrates in untreated SS vs. SS-3BN (A vs. B and F vs. G). However, after radiation, mast cell infiltrates increased, and the number of mast cells was significantly higher in the SS-3BN rats after both 24 × 1 (SS vs. SS-3BN; C and D) and 9 Gy × 5 (SS vs. SS-3BN; H and I). This is summarized for 24 Gy × 1 (E) and 9 Gy × 5 (J). *P < 0.05. Values are means ± SE.