Cartilage:
• Tough, Flexible and Avascular Connective Tissue
• With a Distinctive Extracellular Matrix
◦ Containing:
‣ Collagen
‣ Elastic Fibers
‣ Hyaluronic Acid
‣ Proteoglycans
‣ Glycoproteins
• Consists of Chondrocyte Cells embedded in ECM cavities
called Lacunae
• Three Types of Cartilage
◦ Hyaline Cartilage: Most Common with Type II Collagen
most abundant
◦ Elastic Cartilage: Elastic Fibers in combination
with Collagen Type II
◦ Fibrocartilage: Coarse with Type I Collagen
• The Cartilage is surrounded by Perichondrium
◦ This sheath of surrounding Tissue forms an interface between Cartilage and
Tissue Supported by Cartilage
◦ Perichondrium contains Vascular Components, Lymphatics and Nerve Tissue that
Support the Avascular Cartilage.
HYALINE CARTILAGE: smooth low friction surface in joint, structural support for
respiratory tracts
• Most Common type found in the body
• Also serves as temporary skeleton of the fetus
• Location:
◦ Articular Surfaces of Moveable Bones(Long Bones)
◦ Wall of Respiratory Passages(Nose, Larynx, Trachea,
Bronchi)
◦ Ventral End of Ribs where they articulate with
Sternum
◦ Epiphyseal Plates of Long Bone
• Matrix:
◦ 60-70% of wet matrix is water
◦ 30-40% is Aggrecan which is includes:
‣ Type II Collagen
‣ Sulfated Proteoglycans: Chondroitin Sulfate,
Dermatan Sulfate, Keratin Sulfate which bind as
side chains to->
• Sulfated PGs are negatively charged and are able
to bind water
• The negative charged also repel GAG complexes
from each other and increase the matrix volume
‣ Glycosaminoglycans: Hyaluronic Acid.
◦ The Aggrecan PG Complex hold water and Type II Collagen
together.
◦ Chondronectin a multi-adhesive glycoprotein which
adheres Chondrocytes to ECM
◦ Territorial Matrix the area directly around the
Chondrocytes stains more deeply than the adjacent
Interterritorial Matrix, due to differences in ECM
Composition
‣ Interterritorial Matrix Contains more
Collagen and has glassy eosinophilic
appearance
‣ Territorial Matrix contain more Sulfated
Glycoproteins and less collagen therefore
appears more basophilic
◦ Basophilic
CHONDROCYTES
• Under Indirect stimulation of Pituitary-Derived
Growth Hormone Somatotropin, the endocrine
release from live of Insulin-like growth factor
Somatomedin causes stimulation of Chondrocytes.
• Chondrocytes metabolize glucose through
anaerobic glycolysis which shows the avascular
state of the cartilage.
• They are usually Elliptical/Flat(Chondroblasts)
• Tough, Flexible and Avascular Connective Tissue
• With a Distinctive Extracellular Matrix
◦ Containing:
‣ Collagen
‣ Elastic Fibers
‣ Hyaluronic Acid
‣ Proteoglycans
‣ Glycoproteins
• Consists of Chondrocyte Cells embedded in ECM cavities
called Lacunae
• Three Types of Cartilage
◦ Hyaline Cartilage: Most Common with Type II Collagen
most abundant
◦ Elastic Cartilage: Elastic Fibers in combination
with Collagen Type II
◦ Fibrocartilage: Coarse with Type I Collagen
• The Cartilage is surrounded by Perichondrium
◦ This sheath of surrounding Tissue forms an interface between Cartilage and
Tissue Supported by Cartilage
◦ Perichondrium contains Vascular Components, Lymphatics and Nerve Tissue that
Support the Avascular Cartilage.
HYALINE CARTILAGE: smooth low friction surface in joint, structural support for
respiratory tracts
• Most Common type found in the body
• Also serves as temporary skeleton of the fetus
• Location:
◦ Articular Surfaces of Moveable Bones(Long Bones)
◦ Wall of Respiratory Passages(Nose, Larynx, Trachea,
Bronchi)
◦ Ventral End of Ribs where they articulate with
Sternum
◦ Epiphyseal Plates of Long Bone
• Matrix:
◦ 60-70% of wet matrix is water
◦ 30-40% is Aggrecan which is includes:
‣ Type II Collagen
‣ Sulfated Proteoglycans: Chondroitin Sulfate,
Dermatan Sulfate, Keratin Sulfate which bind as
side chains to->
• Sulfated PGs are negatively charged and are able
to bind water
• The negative charged also repel GAG complexes
from each other and increase the matrix volume
‣ Glycosaminoglycans: Hyaluronic Acid.
◦ The Aggrecan PG Complex hold water and Type II Collagen
together.
◦ Chondronectin a multi-adhesive glycoprotein which
adheres Chondrocytes to ECM
◦ Territorial Matrix the area directly around the
Chondrocytes stains more deeply than the adjacent
Interterritorial Matrix, due to differences in ECM
Composition
‣ Interterritorial Matrix Contains more
Collagen and has glassy eosinophilic
appearance
‣ Territorial Matrix contain more Sulfated
Glycoproteins and less collagen therefore
appears more basophilic
◦ Basophilic
CHONDROCYTES
• Under Indirect stimulation of Pituitary-Derived
Growth Hormone Somatotropin, the endocrine
release from live of Insulin-like growth factor
Somatomedin causes stimulation of Chondrocytes.
• Chondrocytes metabolize glucose through
anaerobic glycolysis which shows the avascular
state of the cartilage.
• They are usually Elliptical/Flat(Chondroblasts)
