FIGURE 7. Longitudinal sections of the proximal, middle, and distal area of control flaps (white bars), heat shock-preconditioned flaps (gray bars), and heat shock-preconditioned flaps treated with SnPP-IX (black bars). Note the massive interstitial edema formation in the middle area of control flaps (B and J) and desiccation of the tissue distally, reflecting necrosis (C and J). Heat shock preconditioning reduces edema formation in the middle area (E and J) and prevents necrosis in the distal part (F and J). This protection is completely blunted by SnPP-IX teatment (H, I, and J). Data are mean ± SEM. *P < 0.05, **P < 0.001 versus control. ^#P < 0.05, ^##P < 0.001 versus heat shock.