| 1. | Venule |
| 2. | Skeletal striated muscle cell |
| 3. | Loose connective tissue with fibrocyte |
| 4. | Capillary |
| 5. | Mast cell |
Dieses Bild zeigt eine Venole, die von quergestreiften Skelettmuskelzellen umgeben ist. Zwischen Venole und den einzelnen Skelettmuskelzellen liegt lockeres Bindegewebe, in das Kapillaren, Fibrozyten und eine Mastzelle eingelagert sind. Der Zellleib der Mastzelle ist rund bis oval, der Zellkern in der Mitte gelegen. Ihr Zytoplasma ist mit basophilen, metachromatischen Granula gefüllt. Im Bindegewebe um die Mastzelle liegen ebenfalls Granula, die bereits von ihr abgegeben wurden.
 | Venule |
 | Skeletal striated muscle cell |
 | Loose connective tissue with fibrocyte |
 | Capillary |
 | Mast cell |
|
Semi-thin sections are often stained by Richardson technique with a blue dye, Methylene blue Azure II.
Basophilic and osmiophilic structures stain blue, and metachromatic structures turn red-violet.
Semi-thin sections of tissue specimens are generally prepared for the light microscopic examination before ultra-thin sections are prepared for examination under the transmission electron microscope (TEM). Semi-thin sections are thinner than other sections commonly used for light microscopy.
The embedding agent for TEM examination is a plastic resin, which is harder than paraffin. Since plastic resin cannot be detached easily and without creating artifacts, in contrast to paraffin, there exist only few suitable staining techniques for tissue embedded in plastic resin. Richardson stain is one of them.
In den Sekretgranula der
Mastzellen sind Überträgerstoffe
enthalten, die auf verschiedene Reize ausgeschüttet werden. Wichtige Überträgerstoffe
sind Histamin und Heparin.
Histamin erweitert die Arteriolen und Venolen und erhöht die Kapillarpermeabilität. Die
Gefäßerweiterung steigert die Durchblutung. Durch die Permeabilitätserhöhung kommt es
zum Ödem. An der Haut zeigen sich diese Reaktionen durch Rötung, Quaddelbildung und
Juckreiz. Heparin ist eine gerinnungshemmende Substanz.
Magnification:
64x
Magnification:
320x
Magnification:
320x
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!