Hemacolor-stained threadlike structures in the rat abdominal subcutaneous tissue. (a) Typical example of the distribution of threadlike structures (white arrows) on the subcutaneous area stained by Hemacolor. ((b) and (c)) Threadlike structures (dotted squares marked as “b” and “c” in (a)) composed of the vessels (arrowheads) that connect the nodes (arrows). Note that the node structures are multibranched (white arrows) from the nodes, and the vessel structures are distributed either on or beneath the subcutaneous surface (two-way dotted white arrows and open arrowheads). Note that the blood vessels (BVs, asterisks) maintain their red color and that threadlike structures are aligned in either a vertical or horizontal direction (yellow arrows). Note the blood vessels around the branching points of the threadlike structures (asterisks).