MUCOUS TUBULAR GLANDS- 1
Mucous tubules are a particular type of tubular gland that is very common in the body. They are found in various locations in the digestive tract (buccal mucosa, salivary glands, esophagus), respiratory system and other systems.
These glands can be placed isolated and scattered (for example, within the connective tissue of the tongue and the walls of the cheeks and lips) or in large clusters forming voluminous anatomical structures (for example, the sublingual salivary glands).
The secretion of these glands is mainly composed of mucus, a material rich in a group of glycoproteins called mucins, that has a slightly viscous consistency.
The secretory portion of the mucous tubules is shaped as a tubule, the length of which can vary considerably, as can its shape, which can range from almost straight to quite convoluted and branched.
The figure shows a diagram of a mucous tubule that is quite simple, short and straight. Its secretory portion (on the left) is larger than the conducting portion (its excretory duct), on the right. The lumen of the secretory portion is usually wide.
The secretory cells are prismatic or pyramidal, their cytoplasm is usually not well stained, slightly basophilic and appears to be vacuolated. This aspect is due to the fact that mucous secretion stains poorly with hematoxylin and eosin.
The nuclei of these cells are quite characteristic. They are elongated, have condensed chromatin and are located in the basal portion of the cell, generally parallel to the basal lamina.
These glands can be placed isolated and scattered (for example, within the connective tissue of the tongue and the walls of the cheeks and lips) or in large clusters forming voluminous anatomical structures (for example, the sublingual salivary glands).
The secretion of these glands is mainly composed of mucus, a material rich in a group of glycoproteins called mucins, that has a slightly viscous consistency.
The secretory portion of the mucous tubules is shaped as a tubule, the length of which can vary considerably, as can its shape, which can range from almost straight to quite convoluted and branched.
The figure shows a diagram of a mucous tubule that is quite simple, short and straight. Its secretory portion (on the left) is larger than the conducting portion (its excretory duct), on the right. The lumen of the secretory portion is usually wide.
The secretory cells are prismatic or pyramidal, their cytoplasm is usually not well stained, slightly basophilic and appears to be vacuolated. This aspect is due to the fact that mucous secretion stains poorly with hematoxylin and eosin.
The nuclei of these cells are quite characteristic. They are elongated, have condensed chromatin and are located in the basal portion of the cell, generally parallel to the basal lamina.
