Fig. 6
Three representative proximal coronary lesion phenotypes detected in 10 month-old Tg53-lsd rats. (A) One type of Tg53-lsd proximal coronary (≈200 microns) lesion comprised predominantly of macrophage foam cells with collagen-rich areas (blue), inflammatory cell (
) adhesion at the shoulder and presence in adventitia (ad); internal elastic lamina is intact; bar = 25 microns; Masson trichrome stain. (B) α-actin immunostained (red) smooth muscle cells in the media; none in lesion. Internal elastic lamina is intact; lesion foam cells are macrophage ED1(+) (data not shown); bar = 25 microns. (C) High magnification reveals intact internal elastic lamina; inflammatory cell () adhesion at lesion shoulder and presence in adventitia; bar = 10 microns. (D) PTAH-stained fibrin in intraplaque thrombi (yellow ); internal elastic lamina is intact; bar=10 microns. (E) A second proximal coronary (≈350 microns) lesion phenotype: eccentric intimal lesion with smooth muscle cells. Few smcs are noted in lesion-side media compared to non-lesion side media; bar = 50 microns; Masson trichrome stain. (F) High magnification of E reveals intact endothelium and internal elastic lamina, foam cells, intimal smooth muscle cells (➨), intraplaque red blood cells and microthrombi (yellow 
); bar = 10 microns. (G) MMP3 immunostaining in lesion smooth muscle cells (➨) and macrophage foam cells; light MMP3 immunostaining detected in lesion-side media; endothelium is intact; bar = 10 microns. (H) TIMP3 immunostaining in macrophage foam cells; none in lesion smooth muscle cells (➨); bar = 10 microns. (I) A third proximal coronary (≈350 microns) lesion phenotype that is minimally occlusive; bar = 50 microns. (J) α-actin immunostained smooth muscle cells (red) in intimal lesion and lesion-side media; bar = 25 microns. (K) MMP3 immunostaining in macrophage foam cells but not in intimal smooth muscle cells (➨); some staining in media smooth muscle cells and foam cells; bar = 10 microns. (L) VEGF immunostaining in macrophage foam cells and endothelial cells (▽) in lesion analyzed in panel E; no VEGF+ neovessels; delipidated extracellular lipid; bar = 10 microns. Note: Endothelium (▽); internal elastic laminae (➩), adventitia; (fc), foam cells; (m), media.