Postinflammatory increase of lymphatic absorption from the peritoneal cavity: role of diaphragmatic stomata.

During the healing phase of a chemical peritonitis in rats, absorption of various inocula from the peritoneal cavity into the draining lymph nodes is increased. Heretofore, this phenomenon has been attributed to fibrosis and shrinkage of the greater omentum. The loss of the sequestering function of the omentum allows the inoculum more ready access to the lymphatic vessels in the diaphragm where it is absorbed. In the present work, it is demonstrated that the chemical peritonitis also widens the stomata in the roofs of the diaphragmatic lymphatic lacunes. Both increased access and larger openings contribute to enhanced lymphatic absorption in the postinflammatory state.