[The human peritoneum and human peritonitis in ultrastructural and immunohistochemical studies].

This paper describes observations of the normal and irritatingly changed morphology of the human peritoneum and about alterations in human peritonitis. The results were obtained by transmission- and scanning electron microscopy, immunohistochemical reactions, and other supplementary light microscopic investigations on surgically collected tissue material. Special attention was given to the superficial structure and the openings of the peritoneum. The superficial liquid film and the microvilli of the mesothelium are influenced by irritative conditions. In the human peritoneum, there are separated areas of small high and of large flat mesothelial cells. The small-cell areas of the peritoneum are connected with openings, special mesothelial cell glades, and cell migrations from deeper parts. There are signs of mesothelial secretion into the peritoneal cavity from mesothelial cells and intercellular spaces of the mesothelium too. The stomata--openings of the peritoneum--are of conditioned character. These depends upon the state of the superficial mesothelium and upon topical loci between the mesothelial cells. Special attention requires the so-called Dreierpunkt. In peritonitis, there are also openings in the fibrin layer. On this condition, the superficial layer of mesothelium mostly becomes destroyed. The keratin reaction is the most essential among the immunohistochemical investigations. It allows to demonstrate preserved mesothelial cells in the deepness of inflammatory tissue in peritonitis.