Page 48 - Headlines Histology2024_Neat
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II) Dense connective tissue
• The fibers are more abundant than cells and amorphous ground substances.
According to the arrangement of its fibrous component, two types are
identified:
a. Dense irregular connective tissue
• It is formed of the same cell types like the loose connective tissue (all
connective tissue cell type), although fibroblasts usually predominate, they
are inactive with highly condensed nuclei and minimal cytoplasm.
• The collagen fibers predominate, and they are arranged in coarse irregular
interwoven bundles with very narrow space in-between.
• It is found in lamina propria of the initial portion of the digestive tract, the
capsule of the lung, the capsule of various organs (spleen, liver, kidney,
testis), fascia, joint capsule and dermis.
b. Dense regular connective tissue
1. Dense regular collagenous (tendon)
• The tendon consists of bundles of parallel collagen fibers that are bounded
together by sparse, loose connective tissue contains small blood vessels,
nerves and active fibroblasts (peritenteneum interna).
• The peritenteneum interna is continuos with the peritendineum externa that
is a loose connective tissue capsule that cover the outer surface of the
tendon.
• The active fibroblasts that are located in the loose connective tissue layer
between the bundles are responsible for the repair of tendons whenever the
needs arise.
• The fibrocytes located between the collagen fibers are inactive cells and
appear as long, flat cells with wing-like cytoplasmic processes extending
between adjacent collagen fibers, giving them a stellate appearance (bird
cells) in cross sections.
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