TABLE 4.
Histological composition of intimal lesions at different topographic locations determined at the age of 21 months in heterozygous LDLr-deficient rabbits fed a 0.15% cholesterol diet initiated at the age of 3 months and in homozygous LDLr-deficient rabbits
| Ascending Thoracic Aorta | Descending Thoracic Aorta | Abdominal Aorta Kidney | Abdominal Aorta Bifurcation | |
|---|---|---|---|---|
| Collagen (% intimal area) | ||||
| LDLr+/− diet | 39 ± 1.5 | 21 ± 1.5 | 26 ± 1.9 | 32 ± 2.3 |
| LDLr−/− | 30 ± 2.0*** | 21 ± 1.9 | 21 ± 1.3* | 26 ± 2.1 |
| Smooth muscle cells (% intimal area) | ||||
| LDLr+/− diet | 0.71 ± 0.092 | 0.61 ± 0.093 | 0.98 ± 0.14 | 1.7 ± 0.22 |
| LDLr−/− | 0.64 ± 0.19 | 1.6 ± 0.21*** | 1.0 ± 0.10 | 1.1 ± 0.17 |
| Macrophages (% intimal area) | ||||
| LDLr+/− diet | 1.0 ± 0.086 | 1.3 ± 0.20 | 1.2 ± 0.20 | 1.3 ± 0.23 |
| LDLr−/− | 0.89 ± 0.10 | 0.76 ± 0.096* | 0.99 ± 0.22 | 1.2 ± 0.40 |
| Oil Red O area (% intimal area) | ||||
| LDLr+/− diet | 11 ± 0.65 | 5.7 ± 0.26 | 7.8 ± 0.42 | 7.3 ± 0.44 |
| LDLr−/− | 9.0 ± 0.52** | 6.2 ± 0.19 | 7.3 ± 0.35 | 6.1 ± 0.41* |
| LPL (% intimal area) | ||||
| LDLr+/− diet | 3.6 ± 0.26 | 3.4 ± 0.40 | 3.6 ± 0.37 | 4.8 ± 0.34 |
| LDLr−/− | 4.2 ± 0.43 | 5.8 ± 0.67** | 3.9 ± 0.41 | 5.1 ± 0.50 |
| Apo B (% intimal area) | ||||
| LDLr+/− diet | 6.3 ± 0.89 | 5.5 ± 0.52 | 4.7 ± 0.45 | 4.8 ± 0.79 |
| LDLr−/− | 6.1 ± 0.84 | 9.7 ± 1.1** | 6.6 ± 0.88 | 5.9 ± 1.2 |
| Apo E (% intimal area) | ||||
| LDLr+/− diet | 11 ± 1.1 | 10 ± 0.51 | 12 ± 1.0 | 9.1 ± 0.88 |
| LDLr−/− | 6.2 ± 0.69*** | 9.9 ± 0.73 | 5.9 ± 0.68*** | 4.9 ± 0.68*** |
Data are pooled for both sexes (n = 29 for LDLr+/− diet and n = 19 for LDLr−/−) and represent means ± SEM. The contribution of male and female rabbits to pooled data is identical as in Table 3. For each parameter, the relative content as percentage of the intimal area was determined within the red/brown color range of the spectrum on high resolution images of complete cross-sections. For the relative collagen content, Sirius red stained slides were observed under polarized light and the red-colored collagen fibers were quantified as percentage of the intimal area. All data were obtained by computer assisted image analysis. *: P < 0.05, **: P < 0.01, ***: P < 0.001 for comparison of LDLr+/− diet rabbits versus LDLr−/− rabbits.