Orientation, anisotropy, clustering, and volume fraction of smooth muscle cells within the wall of porcine abdominal aorta

We analyzed tissue samples of the normal porcine abdominal aorta using stereological assessment of histological sections through the tunica media layer. The results demonstrated that the local volume fraction of smooth muscle cells within tunica media does not differ among samples taken round the circumference of the artery, and that volume fraction can be assessed in sections stained with green trichrome as well as with immunohistochemistry against actin. The distribution of angles between the long axes of nuclei of the smooth muscle cells and the radial direction was different from normal. The profiles of smooth muscle cells were distributed in an isotropic, but an inhomogeneous manner