Basal lamina: Difference between revisions
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''' | '''Basal lamina''' is a layer of extracellular material separating [[Epithelium|epithelial tissue]] from [[Mechanical characteristics of connective tissue|connective tissue]]. The thickness of the basal lamina is 30-100 nm. | ||
https://upload.wikimedia.org/wikipedia/commons/6/65/Basal_lamina.jpg | https://upload.wikimedia.org/wikipedia/commons/6/65/Basal_lamina.jpg | ||
== | ==Function== | ||
* | *This is a selective barrier between epithelial and connective tissue that is important for the interaction, placement and orientation of epithelial cells. | ||
* | *If it is disturbed, there is [[Invasion|invasion]] of epithelial cells into connective tissue (in cancers) or vice versa (e.g. in the growth of blood vessels). | ||
* | *The basal lamina may contain pores where functional communication between the two tissues is needed (e.g. intestinal villi, Peyer's patches).<br /> | ||
__NOTOC__ | __NOTOC__ | ||
== | ==Construction== | ||
https://upload.wikimedia.org/wikipedia/commons/b/b7/Hemidesmosomes_showing_interaction_between_integrins_and_laminin.jpg | https://upload.wikimedia.org/wikipedia/commons/b/b7/Hemidesmosomes_showing_interaction_between_integrins_and_laminin.jpg | ||
It contains two layers: | |||
#'''Lamina lucida''' | #'''Lamina lucida''' | ||
#* | #*A light layer that adheres to the base of the epithelial [[Cell|cell]]. | ||
#* | #*It is attached to cells by hemidesmosomes and anchoring filaments (molecules of integral membrane proteins integrins). | ||
#* | #*It consists mainly of laminin.[[File:Hemidesmosomes showing interaction between integrins and laminin.jpg|alt=|preview|connection of basal cell with basal lamina]] | ||
#'''Lamina densa''' | #'''Lamina densa''' - electron-dense layer 20-90 nm thick. | ||
#* | #*It has a felt-like character. | ||
#* | #*The lamina reticularis is connected to the lamina dense by a system of anchoring fibrils. | ||
#* | #*The lamina densa consists mainly of [[Collagen|collagen]] type IV. | ||
'''Lamina reticularis''' | '''Lamina reticularis''' - a thin layer of reticular fibers and microfibrils of elastic fibers. | ||
*Lamina reticularis | *Lamina reticularis is a product of fibrous tissue cells. | ||
* | *It consists of: | ||
** | **collagen III (reticular fibers), | ||
** | **collagen VII (anchoring fibrils), | ||
** | **fibrillin (microfibrils of elastic fibers). | ||
The term basal lamina is often confused with the term basement membrane. '''Basal membrane = lamina basalis + lamina reticularis.''' | |||
*''' | *'''In the light microscope we do not see the basal lamina, but the basement membrane.'''<br /><br /> <br /> | ||
<noinclude> | <noinclude> | ||
== | ==Links== | ||
=== | ===Related Articles=== | ||
*[[ | *[[Epithelium]] | ||
*[[ | *[[Tissue]] | ||
=== | ===References=== | ||
* {{ | * {{Citation | ||
| | | type = book | ||
| isbn = 978-80-246-1860-9 | | isbn = 978-80-246-1860-9 | ||
| | | surname1 = Vajner | ||
| | | name1 = Ludek | ||
| | | surname2 = Carbon | ||
| | | name2 = George | ||
| | | surname3 = Konrádová | ||
| | | name3 = Václava | ||
| | | title = Medical Histology. 1, Cytology and General Histology | ||
| | | edition = 1st | ||
| | | place = Prague | ||
| | | publisher = Karolinum | ||
| | | year = 2010 | ||
| | | range = 112 | ||
}} | }} | ||
</noinclude> | </noinclude> | ||
[[ | [[Category:Histology]] |
Revision as of 18:40, 12 January 2023
Basal lamina is a layer of extracellular material separating epithelial tissue from connective tissue. The thickness of the basal lamina is 30-100 nm.
Function
- This is a selective barrier between epithelial and connective tissue that is important for the interaction, placement and orientation of epithelial cells.
- If it is disturbed, there is invasion of epithelial cells into connective tissue (in cancers) or vice versa (e.g. in the growth of blood vessels).
- The basal lamina may contain pores where functional communication between the two tissues is needed (e.g. intestinal villi, Peyer's patches).
Construction
It contains two layers:
- Lamina lucida
- A light layer that adheres to the base of the epithelial cell.
- It is attached to cells by hemidesmosomes and anchoring filaments (molecules of integral membrane proteins integrins).
- It consists mainly of laminin.
- Lamina densa - electron-dense layer 20-90 nm thick.
- It has a felt-like character.
- The lamina reticularis is connected to the lamina dense by a system of anchoring fibrils.
- The lamina densa consists mainly of collagen type IV.
Lamina reticularis - a thin layer of reticular fibers and microfibrils of elastic fibers.
- Lamina reticularis is a product of fibrous tissue cells.
- It consists of:
- collagen III (reticular fibers),
- collagen VII (anchoring fibrils),
- fibrillin (microfibrils of elastic fibers).
The term basal lamina is often confused with the term basement membrane. Basal membrane = lamina basalis + lamina reticularis.
- In the light microscope we do not see the basal lamina, but the basement membrane.
Links
Related Articles
References
- {{#switch: book
|book =
Incomplete publication citation. VAJNER, Ludek, George CARBON and Václava KONRÁDOVÁ. Medical Histology. 1, Cytology and General Histology. Prague : Karolinum, 2010. 112 s. 1st; 978-80-7262-438-6.
|collection =
Incomplete citation of contribution in proceedings. VAJNER, Ludek, George CARBON and Václava KONRÁDOVÁ. Medical Histology. 1, Cytology and General Histology. Prague : Karolinum, 2010. 112 s. 1st; {{ #if: 978-80-246-1860-9 |978-80-7262-438-6} } |article = Incomplete article citation. VAJNER, Ludek, George CARBON and Václava KONRÁDOVÁ. 2010, year 2010,
|web =
Incomplete site citation. VAJNER, Ludek, George CARBON and Václava KONRÁDOVÁ. Karolinum, ©2010.
|cd =
Incomplete carrier citation. VAJNER, Ludek, George CARBON and Václava KONRÁDOVÁ. Karolinum, ©2010.
|db =
Incomplete database citation. Karolinum, ©2010.
|corporate_literature =
VAJNER, Ludek, George CARBON and Václava KONRÁDOVÁ. Medical Histology. 1, Cytology and General Histology. Prague : Karolinum, 2010. 112 s. 1st; 978-80-7262-438-6} }