Salivary gland
The salivary glands produce the Salive which is the liquid which bathes the Bouche. Saliva has as a role to humidify the mucous membranes of the digestive Système higher, to take part at the first stages of the Digestion and to facilitate the progression of food of the Pharynx to the esophagus and the Estomac. The salivary glands are glands with mode of Sécrétion exocrine.
Anatomy of salivary glands
The three principal pairs of salivary glands are:
- the sublingual glands, they pour saliva in the mouth, via channels which are brought together under the language. The two principal ones are the channels of Walther and of Rivilus
- the submaxillary glands, they pour saliva in the mouth via the channel of Wharton.
- the glands Parotid S, largest, they are located on each side of the face below and in front of the ears. They pour saliva on the level of the cheek by the channel of Stenon, a sufficiently large channel so that one can feel it by gripping the interior and the outside of the cheek with the fingers.
Histology
The salivary glands are locked up in a conjunctive capsule fibrous and are divided into lobules. The blood-vessels and the Nerf S penetrate in gland by the Hile and ramify in the lobules. The secreting unit of the Parenchyme lobulaire is the adénomère. It consists of secreting cells forming of the agglomerates called acini (acinus in the singular) hollow whose cavity (the lumen) is prolonged by an intercalated channel. The intercalated channels of several acini meet to form the striated channel (or channel of Pflüger). Each striated channel pours secretions of the lobule from which it is resulting in the interlobular channel which circulates in the interlobular partitions. The interlobular channel constitutes the channel excretor of salivary gland and emerges in the oral cavity.
Surrounding each acinus with the manner of an octopus, the myo-epithelial cells are similar in all points with the smooth muscular cells. Contractile, they would play a part in the expulsion of the products of secretion.
Cytology
Séreuses cells: They secrete a Salive without Mucine. Of pyramidal form, their round core occupies the basal third. They are rich in grains of secretion accumulated in the apical pole, these grains are strongly coloured with basic dyes masking the aspect of the cells in optical microscopy.
Mucous cells: They secrete viscous saliva, rich in mucins. Of big size, their core of angular form is pushed back completely in the basal part of the cell. The endoplasmic reticulum and the grains of secretion are abundant and the very developed Golgi. The grains have the appearance of pale droplets to coloring.
One classifies salivary glands according to the cellular type which they contain:
- Parotid: almost exclusively of the séreuses cells;
- Submandibulaire : mixed, with prevalence of séreuses cells;
- Sublingual: mixed, with prevalence of mucous cells;
- additional Glands: mixed or mucous cells, except for the lingual dorsals (séreuses).
Role in the diseases
See Mumps ( parotiditis epidemica ) and Syndrome of Sjögren. The most frequent pathology of submaxillary glands is the salivary Lithiase. It is about the formation of one: calculation which stops partially or completely the excretion of saliva. This salivary damning up can cause a swelling under jawbone, of the pains, even a local infection. One also meets tumors of salivary glands. They are in general benign (pleomorphic adenoma for example), but can also be malignant.
External bonds
- Illustration
Fiu-vro: Sülenääreq Simple: Salivary nipple
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