ABSTRACT
In fifteen human fetuses spcimens the peritoneal stomata were studied with SEM and TEM, and measured by image processing system. In order to prove that the peritoneal stomata are the passageway of absorbed matter from the peritoneal cavity, animal experiments were made. There are two types of the mesothelial cells on diaphragmatic peritoneum, i. e. the cuboidal cells and the flattened cells. The peritoneal stomata, which arranged in clusters or strips, were only found between the cuboidal cells. The shape and size of the stomata were often irregular. The average area of the stoma on the muscular portion is 10.43?1.61?m~2, while on the tendinous portion is 7.93?1.67?m~2. The connective tissue underlies below the stomata, under which no basement membrane was found. Many lymphatic capillaries were observed in the connective tissue, which may promote absorption of matter from the peritoneal cavity. In animal experiments, some particles of trypan blue were absorbed through the stomata of rabbit diaphragmatic peritoneum. The authors consider that the stomata, are first observed in human, are important pathway for draining matter from the peritoneal cavity.