Tooth (Homo) (longitudinal section through decalcified tooth, HE)

A. Pulp of the tooth – yelly-like connective tissue with blood capillaries and fine nerve fibers; arterioles and venules are oriented longitudinally. The layer of odontoblasts (cells of dentin) is situated on the external surface of the pulp.

B. Dentin – underlying tissue of dental crown, neck and root(s). Dentin shows fine striation, caused by dentin tubules (contain the cytoplasmic processes of odontoblasts); dentin is stained in red or red-violet color, except thin layer near the odontoblasts – predentin (is not calcified) and peripheral layer below cementum and enamel (is irregularly calcified), dentin is pale in this layers.

C. Enamel – is not present in decalcified tooth (it dissolves during decalcification).D. Cementum – covers the root(s) of the tooth; the thickest layer is on the root apex(es); it is not

possible to distinguish primary (acellular) and secondary (cellular; with cementocytes) cementum in the light microscope.

E. Periodontium – bundles of collagenous fibers, which hold the dental root in bone alveolus (rarely present in slides).

http://www.kgu.de/zmorph/histopatho/histo3/data/organe/de/JA1_046_b.html

Oesophagus (Homo) (cross section, HE or HES)

A. Tunica mucosa:1. lamina epithelialis mucosae – stratified squamous epithelium,2. lamina propria mucosae – areolar (loos) connective tissue (mucous glands and solitary lymph

nodules can be present in upper and lower 1/3 of esophagus),3. lamina muscularis mucosae – bundles of smooth muscle cells oriented predominantly

longitudinally.B. Tela submucosa – wide layer of areolar connective tissue, contains vessels and mixed glands - gll.

oesophageae.C. Tunica muscularis (externa) – two layers: inner - circular, outer - longitudinal; in connective tissue

layer between inner and outer muscle layers - plexus myentericus Auerbachi;1. the upper third of gullet – skeletal muscle tissue,2. the middle third of gullet – skeletal and smooth muscle tissue,3. the lower third of gullet – smooth muscle tissue.

D. Tunica adventitia – loos connective tissue, joins the organ with neighbourhood.

 

Tunica mucosae:

stratified squamous epithelium

lamina propria mucosae

lymph.nodule

lamina muscularis mucosae

Tela submucosa mixed glands

inner circular layer of tunica muscularis externa

OESOPHAGUS

Fundus ventriculi (Homo)(vertical section to the surface of mucosa, HE)

A. Tunica mucosa – see areae gastricae and foveolae gastrice 1. lamina epithelialis mucosae – tall, simple columnar epithelium with secretory granules in the cell

apexes,2. lamina propria mucosae – areolar connective tissue with tubular glands - gll. gastricae propriae. In

each gland, basis (near lamina muscularis mucosae), body and neck is distinguished; the gland is opened into the gastric pit throughout the neck. The cells of gll. gastricae:– chief cells - (pepsinogenous) - located predominantly at the basis, they have prismatic shape

and basophilic cytoplasm,– parietal cells - (HCl cells) - in the body and below the neck, the cells are round triangular, their

cytoplasm is strongly eosinophilic,– the cell of neck - light and columnar in the neck (their product is mucus),– endocrine cells - cannot be identified in slides stained with HE,

3. lamina muscularis mucosae – 2 layers of smooth muscle cells (inner - circular, outer - longitudinal).

B. Tela submucosa - areolar connective tissue with vessels and nerves.C. Tunica muscularis (externa) – 3 layers of smooth muscle cells: oblique, circular and longitudinal

layer.D. Tunica serosa:

1. simple squamous epithelium - mesotel,2. lamina propria serosae – thin layer of collagenous connective tissue.

areae gastricae (13, 14)

mucosa (9) = epithelium (11) + l. propria with glands (10) + l. muscularis (8)

submucosa (7)

3-layred external muscle coat (3 = 4 + 5 + 6)

serosa (1 - mesotel + 2 - connect.tissue)

Cardia

fundus and body

Intestinum tenue - jejunum (Homo) (longitudinal section through the wall, HE)

Prior to study in microscope see plicae semicirculares Kerckringi, which are formed by mucosa and submucosa.A. Tunica mucosa – typical organization of the surface: villi intestinales - intestinal villi (their axis is

made up of reticular connective tissue of lamina propria mucosae) with central lymphatic vessel (lacteal vessel) in each villus; crypts of Lieberkühn - tubular invagination among villi, their bases reach lamina muscularis mucosae:1. Lamina epithelialis mucosae – tall, simple columnar epithelium composed of absorptive cells -

enterocytes and secretory cells:– goblet cells - thei have cup-like shape, flattened nucleus and very pale cytoplasm containing

mucus, goblet cells are diffused in the epithelium and their number increased in aboral direction,

– cells of Paneth - round triangular or pyramidal shape, spherical nucleus, eosinophilic granules in cytoplazm, the cells are located only in basis of crypts of Lieberkühn (these cells are unstained in older slides because the granules are discolored),

– endocrine cells - cannot be identified in slides stained with HE,2. lamina propria mucosae - reticular connective tissue with lymphatic nodules (formes underlying

tissue of intestinal villi and surrounds the crypts of Lieberkühn),3. lamina muscularis mucosae – smooth muscle tissue.

B. Tela submucosa – loose connective tissue, whish also forms the axis of folds of Kerckring (plicae semicirculares Kerckringi).

C. Tunica muscularis (externa) - 2 layers of smooth muscle cells: inner circular and outer longitudinal.

D. Tunica serosa – see description of the stomach.

Duodenum (Homo) (longitudinal section through the wall, HE)

A. Tunica mucosa – typical organization: villi intestinales; crypts of Lieberkühn 1. lamina epithelialis mucosae –simple columnar epithelium composed of absorptive cells

and secretory cells (see descrition of the intestinum tenue) 2. lamina propria mucosae - reticular connective tissue with lymphatic nodules (formes

underlying tissue of intestinal villi and surrounds the crypts of Lieberkühn),3. lamina muscularis mucosae – smooth muscle tissue.

B. Tela submucosa – loose connective tissue whith mucous glands – Brunner´s glands (an important signe of this part of small intestine!).

C. Tunica muscularis (externa) - 2 layers of smooth muscle cells: inner circular and outer longitudinal.

D. Tunica serosa – see description of the stomach.