Fig. 6.

L_p of the rat aorta ex vivo. Figure 1 shows the experimental setup. A: L_p(ΔP) for an excised aorta from 300- to 350-g male SD rats, first without (bold solid) and then with (dashed) the AQP blocker HgCl₂, and then after endothelial denudation (thin solid), with all nine L_p values taken on each vessel. HgCl₂ reduced every vessel's L_p significantly at every pressure. B: replot of these data as means ± SE of the percent drop in L_pt with HgCl₂ versus ΔP. HgCl₂ reduced L_pt (32 ± 4%) at 60 mmHg and less [yet significantly different (P = 0.000026) and nonzero] at 100 (11 ± 2%) and 140 mmHg (5 ± 3%). C: since HgCl₂ does not change L_{pm + I} (Table 5), changes in L_pt reflect changes in endothelium + SI L_{pe + i} (points); numbers above the points are means ± SE of percent drops in L_{pe + i} with HgCl₂. These differences are distinguishable (P < 0.005) for 60 mmHg versus the other pressures only. (This figure and these statistics neglect the lone outlier that showed nearly no difference between L_pt and L_{pm + I}, and thus a huge L_{pe + i}, at 60mmHg only; the mean ± SE for the percent drop including this outlier at 60 mmHg was 56 ± 7.4%). L_{pe + i} dropped by more than half at 60 mmHg. n = 6.