Lymphatic network and nerve plexus in the myenteric layer of the monkey jejunum: a topographic study using an...

The topographic relationship between the lymphatic network and the nerve plexus in the myenteric layer of the monkey jejunum was studied by an enzyme-histochemical method. Identification of the lymphatics was achieved by a 5'-nucleotidase staining method, and the enteric neural components were visualized by acetylcholinesterase staining. A well-developed lymphatic network and a dense nerve plexus were demonstrated throughout the myenteric layer. Numerous segments of the initial lymphatics, with their blind endings at the apical parts, tended to gather toward the ganglion and run along the primary nerve strands. Elements of the tissue interstitium separated the lymphatics from the enteric nerves. Nerve terminals were often located closely beneath the endothelium of the initial lymphatics and were exposed to the subendothelial tissue on the side facing the abluminal surface of the lymphatic endothelium. These findings suggest that the lymph flow in the initial lymphatics might be regulated by the enteric nervous system, and that the transport of tissue fluid by the lymphatics might serve as a suitable microenvironment for the enteric nerves.