Peritoneal cell responses to acute gastro-intestinal inflammation.

Cell changes in the peritoneal exudate induced by an acute localised inflammation due to a small intestinal anastomosis have been studied. The maximum response occurs on the second day. The neutrophil polymorphonuclear leucocyte output on the second is seven times greater in the peritoneal exudate than in the effluent lymph from the gastro-intestinal tract. The fate of the inflammatory cell response of the peritoneal exudate has been studied using thymidine-labelled cell transfer experiments. Some neutrophil polymorphonuclear leucocytes and eosinophils are phagocytosed by monocyte/macrophage cells in the peritoneal cavity. The majority of the neutrophil polymorphonuclear leucocytes and eosinophils migrate through diaphragmatic "stomata" to the parathymic lymph glands via the mediastinal lymphatics.