Blood vessels of the Peyer's patch in the mouse: I. Topographic studies

The topographic distribution of blood vessels in Peyer's patches of mice was studied by light and scanning electron microscopy with whole mounts of flattened gut segments and vascular corrosion casts. Peyer's patches are imbedded in the intestinal wall and share its blood supply. Two to four mural trunks may contribute to the area of the patch. In and around the lymphoid nodules the microcirculation is highly specialized. The nodule is permeated by a meshwork of fine capillaries that is supplied by arterioles entering on the serosal and lateral surfaces. Blood flow to the lymphoid nodule appears tobe monitored by arterial sphincters; the dense lymphatic tissue can also beby passed by arteriovenous communications. An extensive venous network encircles the nodule. Most of these venules are lined by high endothe…