Connective
Tissue Types
Loose connective tissue and dense connective
tissues
These two tissues are distinguished according to
the relative amounts of fibres they contain. Dense
connective tissues are completely dominated by fibres. They are
subdivided according to the spatial arrangement of the fibres in the tissue.
In dense irregular
connective tissue the fibres do not show a clear orientation within the tissue
but instead form a densely woven three-dimensional network. A good example is
the dermis of the skin.
We talk about regular
dense connective tissue if the fibres run parallel to each other. Good examples
of regular dense connective tissue are tendons, ligaments and the fasciae and
aponeuroses of muscles.
Loose connective tissue
is relatively cell rich, soft and compliant. It is also rich in vessels and
nerves. It is best understood as a kind of generalised connective tissue in
which all connective tissue cell types may occur. Loose connective tissue may
occur in some special variants: mucous connective tissue,
reticular connective tissue and adipose tissue.
sections of tendons or ligaments - van Gieson, H&E
|
Muscle-Tendon Junction, rat - van Gieson
In van Gieson stained preparations collagen stains dark red while other
tissue components appear in varying shades of grey (nuclei) and yellow
(cytoplasm). Areas of dense regular connective tissue are usually easy to
identify in these preparations. Coarse collagen fibres are aligned with each
other with only very narrow opens spaces between them. Like in most other
connective tissues, there will be only a few cells between the fibres. Their
cytoplasm is difficult to identify but the nuclei can be seen scattered among
the collagen fibres. Nuclei are often elongated, and their long axis runs
parallel to the course of the collagen fibres
Sketch part of the regular dense connective tissue.
|
sections of skin or non-lactating
mammary gland - H&E, van Gieson, trichrome
|
Non-lactating Breast - H&E
Dense irregular connective tissue forms the dermis of the skin, i.e. the
layer of connective tissue immediately below the epithelium lining the
surface of the skin. Beneath the skin forming the mammae (nipples), dense
connective tissue areas are very extensive. This tissue surrounds the resting
mammary gland. Both the high density of collagen fibres and the their
irregular distribution are easily visible. Again, only a very small fraction
of the tissue is taken up by cells. Like in van Gieson stained preparations,
their cytoplasm is often not visible in H&E stained sections. Dark spots
scattered between the collagen fibres represent the nuclei of the cells.
Draw part of the connective tissue including some
fibrocytes.
The excretory ducts of the mammary glands are called
lactiferous ducts. They are lined by a quite nice stratified columnar
epithelium. If you are working with a section of non-lactating breast look
for the lactiferous ducts in the connective tissue.
|
![thumbnail]( "Connective Tissue Types")
Title:
Connective Tissue Types
by:
om
at
2013-02-15T02:54:00+07:00
Rating: 4.8
of 5 Reviews
Connective Tissue Types