Background: The apoE-/-/LDL-/- double knockout mice are bearing considerable structural homology to human atherosclerosis. We hypothesized, that advanced lesion formation in the renal artery is associated with kidney alterations in these mice.
Methods: Kidneys from apoE-/-/LDL-/- double knockout mice at the age of 80 weeks (n = 6) and C57/BL control mice (n = 5) were infused with Microfil, harvested and scanned with micro-CT (12 mum cubic voxels) and Nano-CT (900 nm cubic voxels). We quantitated the total vascular volume using micro-CT. Number and cross-sectional area (microm2) of glomeruli were measured using histology.
Results: At the age of 80 weeks, the renal total vascular volume fraction decreased significantly (p < 0.001) compared to controls. Moreover, the renal artery showed advanced atherosclerotic lesions with adventitial Vasa vasorum neovascularization. Perivascular inflammation was present in kidneys of apoE-/-/LDL-/- double knockout mice, predominantly involved are plasma cells and leucocytes. Glomeruli cross-sectional area (9959 +/- 1083 microm2) and number (24.8 +/- 4.5) increased in apoE-/-/LDL-/- double knockout mice compared to controls (3533 +/- 398 microm2; 17.6 +/- 3, respectively), whereas 41% of the total number of glomeruli showed evidence for lipoprotein associated glomerulopathy (LPG). Moreover, immunohistochemistry demonstrated capillary aneurysms of the glomeruli filled with factor 8 containing emboli.
Conclusion: The reduced intra-renal total vascular volume is associated with systemic atherosclerosis and glomeruli alterations in the apoE-/-/LDL-/- double knockout mouse model.