Table 1.
Study Groups.
Figure 1.
Ablation effect due to different NTIRE protocols.
The reduction in five of the groups was statistically significant (P<0.001, bars marked with an asterisk). Ablation effect is shown as the percentage of VSMC cells in the treated artery compared with the right carotid artery of the same animal.
Figure 2.
Complete ablation of VSMC population one week following NTIRE.
Complete ablation of VSMC population one week following NTIRE with 90 pulses of 1,750 V/cm (right picture) compared with right carotid artery of the same animal that was used as a control (left picture). Note the complete absence of VSMC cells compared with notable repopulation of the endothelial layer with endothelial cells.
Table 2.
Effect of 10 NITRE pulses.
Table 3.
Effect of 45 or 90 NTIRE pulses.
Figure 3.
Ablation effect of the sub-layers of the Tunica Media.
Inner most, middle and outer sub-layers are in blue, red and green, respectively. Ablation effect is shown as the percentage of VSMC cells in the sub-layer compared with the same sub-layer in the right carotid artery of the same animal. Note the relative sparing of the inner most VSMC cells in all five groups, compared with the complete ablation of VSMC in the outer layers with 1750 V/cm (second and third groups in the figure).
Figure 4.
Effect of NTIRE on blood vessels after one week.
Higher magnification (×40) of the effect of NTIRE on blood vessels after one week. Top picture shows a control artery, middle picture shows the partial effect due to 45 pulses of 875 V/cm (Group 6), lower picture shows a complete ablation of the arterial VSMC population. In the case of the partial effect - all surviving VSMC are located in the innermost layer of the Tunica Media. Also, note in the lower picture the repopulation of the endothelial layer with endothelial cells, compared with total absence of VSMC.
Figure 5.
Conductance change during NTIRE application.
X-axis shows the eight study groups. Y-axis shows the change as the ratio between the conductance value measured at the last electroporation pulse and the value at the first pulse. Groups 3 and 4 (875×10 and 437.5×10, respectively) show no change in conductivity, which correlates well with the no ablation effect (see figure 2). Group 2 (1,750×10) shows partial reduction in conductivity, correlating well with minor ablation effect.
Figure 6.
Left column shows control arteries and right column shows IRE-treated arteries. Top row - EVG stain showing undamaged elastic fibers in IRE-treated arteries (elastic Van Gieson, ×40). Middle row - Masson Trichrome stain showing mild fibrosis in the perivascular area with dominance of collagen fibers in the Tunica Media of the IRE-treated Arteries (Masson Trichrome, ×40). Lower row - Negative staining of both arteries with CD34 antibodies at higher magnification (×60). Note the similar morphology and distribution of the endothelial cells.