The latter is unstained in this preparation. Surrounding each nerve fiber is a delicate connective tissue sheath, the encloneurium. The arteriole shows the component layers. Note the well-defined internal elastic membrane internal to the smooth muscle coat. The intima is an extremely thin layer.
Erythrocytes fill the lumen of the arteriole.
The venule seen here is smaller than the adjacent arteriole. Typically, venules are larger than arterioles. Note that the bulk of the wall is made up of connective tissue adventitia, the other coats being thin and inconspicuous. The stain used in this preparation is useful to differentiate muscular and connective tissue elements. All rights reserved.