Submandibular Gland:Slide 183-1 Submandibular gland H&E View Virtual Slide Slide 183-2 Submandibular gland (homo) 20X, mucicarmine stain [stains mucus red] View Virtual Slide Slide 184 Submandibular gland H&E View Virtual Slide Sublingual Gland:Slide 185-1 Sublingual Gland 40X H&E View Virtual Slide Slide 185-2 Sublingual Gland 40X H&E View Virtual Slide Slide 185A Sublingual gland 20X mucicarmine and H&E stain [stains mucus red] View Virtual Slide Unlike the parotid gland, the submandibular and sublingual glands possess both mucous and serous secretory cells. Slides 183-2 (submandibular) and 185A (sublingual) are stained with mucicarmine, which specifically stains mucus red. Survey the two alternate slides to compare the relative proportions of mucous acini in these two glands. After this, go back to the H&E-stained slides to study the histology of mucous and serous secretory acini. In slide 183 and 184 of the submandibular gland, mucous secretory acini are those that stain lightly. Compare the appearance of mucous and serous secretory cells. The serous cells possess granular cytoplasm and nuclei which are spherical and vesicular in appearance. The mucous cells have pale staining cytoplasm and nuclei which appear to be pushed against the basal cell membrane. Now, observe the blind end of a mucous acinus and note the serous demilune cells View Image that cap this region of the secretory acinus. These demilune cells also have brightly staining granules in their cytoplasm. As an aside, the serous and mucous cells are actually adjacent to each other in vivo, and the formation of these demilunes is actually a fixation artifact (mucous cells swell with traditional fixation techniques and “squeeze out” the serous cells). Even so, the characteristic appearance of demilunes is nonetheless a useful diagnostic for identifying sero-mucous glands. Switch to a lower power and observe the distribution of ducts. Note the presence of large ducts in the connective tissue septae separating the lobules. These are interlobular or excretory ducts View Image and their epithelium appears to be stratified. The intralobular ducts within the lobules are smaller and similar in appearance to those of the parotid gland (i.e. they are striated ducts). The intercalated ducts in the submandibular and sublingual glands are very short and therefore NOT encountered often in sections. Now examine slide 185-1 and 185-2, the sublingual gland, and note the greater prominence of mucous acini and fewer numbers of intralobular ducts than in the submandibular gland. Some lobules in slide 185-1 and 185-2 reveal almost all ducts with a few remaining secretory cells. This represents a pathological transformation of secretory acini to duct-like structures.
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