Figure 2
From: Canine mesenteric artery and vein convey no difference in the content of major contractile proteins
Electron micrographs of a tertiary mesenteric artery branch. Panel A: endothelial cell layer (E), internal elastic lamina (IL), and smooth muscle cells (SM). The long axis of the muscle fibers within tunica media runs at an angle to the circular axis of the vessel wall (Panel B). These cells have ultrastructural characteristics of smooth muscle cells including dense bodies (DB, Panel C) and bands, mitochondria (M, Panel C), sacroplasmic reticulum (SR, Panels C and D), and a basal lamina (BL, Panel D). Elastin (L), collagen fibrils (C), elastic lamina (EL), dense cored vesicles (arrows), small electron lucent vesicles (arrowheads, Panel D). Scale bar is as indicated for each panel.