Transmission electron micrograph of right carotid artery specimens. (A)The smooth muscle cells in the media are spindle-shaped and well-arranged (bar represents 1 μm, magnification × 20 000). (B) The internal elastic lamina is loose. Many lipid droplets deposit in the intima and media.Furthermore, SMCs have died by disintegration into myriad vesicles (bar represents 1 μm, magnification × 10 000). (C)The intima is irregularly thickened and multilaminated, the internal elastic lamina is thickened, and the SMCs grow vertically to the internal elastic lamina(bar represents 2 μm, magnification × 10 000). (D) The smooth muscle cells in the media are disordered and filled with small cell bodies and lipid droplets, the collagen fibrils significantly increase, and the apoptotic bodies, pycnosis of the nuclei could be found(bar represents 5 μm, magnification × 5000).