In der Schilddrüse des Hundes sind die C-Zellen gut zu identifizieren und besser von den Follikelzellen zu unterscheiden als in der menschlichen Schilddrüse. Sie sind einzeln oder in Gruppen in das Follikelepithel eingestreut oder bilden Nester im parafollikulären Bindegewebe.

Legende:

	Follicle wall with simple cuboidal epithelium
	Colloid droplet
	Peripheral vacuole
	Artificial shrinkage cleft
	C-cells (parafollicular)
	Loose fibrous connective tissue

HOPA

Structures	Colour
Nuclei	brown
Cytoplasm	grey-blue
Connective-tissue fibres - Collagen - Reticular - Elastic	blue blue -
Myocytes	grey-blue to grey-green
Erythrocytes	yellow-orange

Dyes:

HOPA = Hemalaun, Orange G, Phosphormolybdenic acid, Aniline blue

Cell nuclei are stained with hemalaun or Weigerts iron-hematoxylin and then counterstained with a dye mixture of orange-phosphormolybden with aniline blue.

Die Ausschüttung von Calcitonin aus den C-Zellen der Schilddrüse führt durch Hemmung der Tätigkeit von Osteoklasten (= Hemmung der Calciumresorption aus dem Knochen) zu einer Senkung des Ca²⁺-Spiegels im Blut, während das Parathormon aus den Nebenschilddrüsen (Glandulae parathyroideae, Epithelkörperchen) den Ca²⁺-Spiegel erhöht. Das Hormon Calcitonin der Schilddrüse und das Parathormon der Epithelkörperchen wirken antagonistisch. Das Parathormon vermindert die Reabsorption von Calcium in der Niere und steigert den Einbau von Calcium und Phosphat in den Knochen.
Eine Erhöhung des Calciumspiegels löst eine Sekretion von Calcitonin aus.

HistoNet2000 - Help

1. Organization of the screen surface

Right side: histologic specimen
Left side: information about the specimen (above) and general program functions (below)

2.Histologic specimen

Pull the mouse across the histologic specimen for training purposes. A small square with exclamation marks (dynamic labels) will appear where there is an important structure. You should then decide what structure this could be. To check your result, simply click the appropriate square, and the correct label will appear. The option “marked” allows you to see all labels for all structures simultaneously. These can be removed by clicking “unmarked”. This reactivates the dynamic labels.

3. Complementary information

Info: general information about the specimen, as well as a list of the dynamic labels
Drawing: schematic drawing of the specimen
Staining: information about the staining method for this specimen
Knowledge: short texts with basic histologic information, presently deactivated

4. General Program Functions

Home: returns you to the “start” page
Tutor: how to contact the HistoNet Team
Help: Instructions for Use appear
Exit: closes down the HistoNet program
Boxes: goes back to the other specimen of a topic
VM: provides virtual microscopy

We hope you will enjoy working with HistoNet2000 and learn a lot from it!

Specimen Nr. 02B

Specimen:

Staining:

Magnification:

Important structures :

Legende:

HOPA

Dyes:

HistoNet2000 - Help