ABSTRACT
This chapter discusses the major digestive glands and endocrine glands, which contain parenchymal tissues composed of reverting postmitotic radioresistant cells. The large salivary glands have excretory ducts opening into the oral cavity. The sublingual salivary gland, a composite of glands, is a mixed gland more variable in composition than the other salivary glands. Contrary to expectations on the basis of the classification of the parenchymal cells of the salivary glands as reverting postmitotic cells, the salivary glands appear to be moderately radiosensitive functionally, and in parts histo-pathologically. The liver is one of the organs which stores heparin. It also synthesizes protein, such as fibrinogen, which is secreted to the blood, and it forms an antianemic substance which stimulates the regeneration of red blood cells. The liver is essentially a compound tubular, serous, merocrine gland which is highly modified by replacement of tubules by branching and anastomosing cords or plates of epithelial cells and reorganization of the parenchyma into lobular units.
