Cat soleus muscle. Capillary between two muscle fibers. Four deformed erythrocytes (red blood cells) are in the capillary lumen. Vesiculation of the endothelial cytoplasm is due to the large number of pinocytic vesicles. The outer surface of the endothelial cells is covered by an electron opaque "basal lamina" (aka glycocalyx). Another layer of this material covers the surface of each muscle fiber.