SALIVARY GLAND Slides 116,117,118 and 115.
Each section constitutes a portion of a lobe of the gland. The parotid gland is wholly serous in nature. The submandibular and sublingual glands are mixed serous and mucous. Remember that serous cells are usually darker, have round nuclei, and contain secretory (zymogen) granules within their cytoplasm. Mucous cells are usually pale, have a foamy appearance, and have very dark, dense nuclei flattened against the base of the cells.
Look first at slide 116, a mixed salivary gland of the cat. At low power note the connective tissue septa which divide the lobe into lobules. The ducts, nerves and bloodvessels running within the septa are called interlobular; when running among the secretory acini, they are called intralobular. Ducts of both types are very clear in salivaryglands, with a pink cytoplasm and clear, round nuclei. The branching of the duct systemis very evident in this section. As for the secretory acini, you will find both serous and mucous units. Occasionally, you may also see serous demilunes capping the periphery of mucous end pieces. Look with a high power for cellular detail. Many slides contain sections of parasympathetic ganglia lying the glandular septa. Some slides also show alymph node at one end of the gland.