Endochondral Ossification Essay
A) Growth plate and Endochondral ossification:
In order to maintain a healthy skeletal system which is crucial for different organs such as respiratory system, brain, spinal cord and heart, it is very important to have a good development of the skeletal system. Endochondral ossification is the process through which the axial and appendicular skeletons are formed through the formation of a cartilage inter-mediate.
A good model for endochondral ossification is the limb bud where the precursor cells of the mesenchyme condense and then followed by the differentiation of the most central chondrocytes.
Endochondral ossification is a highly regulated process by different signalling like the epidermal growth factor receptor (EGFR), a tyrosine kinase …show more content…
Figure 1:Different zones of the growth plate.
In the upcoming paragraphs, I will discuss the characteristics and the role of each of the growth plate zones in endochondral ossification. I will also present studies (microarray analysis) to study the differential regulation of genes in these zones.
The resting (reserve) zone:
The resting zone consists of resting cartilage cells .The characteristic feature of these cells is that they are small, uniform, compactly located chondrocytes which are present as single cells or in pairs. These cells are rich in lipid and cytoplasmic vacuoles. Moreover, there is more extracellular matrix (ECM) than cells in this zone. This zone is also characterized by having a low rate of proliferation and proteoglycan and collagen type IIB synthesis. The grove of Ranvieer is surrounding this zone (4).
The role of the resting zone in endochondral ossification:
There is an existing possible hypothesis that the resting zone contains chondrocytes (stem cell like cells) which acts as progenitor cells that are able to give rise to chondrocytes that are characterized by having rapid division. Each clone will constitute a cell column that is aligned parallel to the long axis of the bone. When the cells undergo replication, and inorder to keep the columner organization, the two daughters line up parallel to the long axis
In order to maintain a healthy skeletal system which is crucial for different organs such as respiratory system, brain, spinal cord and heart, it is very important to have a good development of the skeletal system. Endochondral ossification is the process through which the axial and appendicular skeletons are formed through the formation of a cartilage inter-mediate.
A good model for endochondral ossification is the limb bud where the precursor cells of the mesenchyme condense and then followed by the differentiation of the most central chondrocytes.
Endochondral ossification is a highly regulated process by different signalling like the epidermal growth factor receptor (EGFR), a tyrosine kinase …show more content…
Figure 1:Different zones of the growth plate.
In the upcoming paragraphs, I will discuss the characteristics and the role of each of the growth plate zones in endochondral ossification. I will also present studies (microarray analysis) to study the differential regulation of genes in these zones.
The resting (reserve) zone:
The resting zone consists of resting cartilage cells .The characteristic feature of these cells is that they are small, uniform, compactly located chondrocytes which are present as single cells or in pairs. These cells are rich in lipid and cytoplasmic vacuoles. Moreover, there is more extracellular matrix (ECM) than cells in this zone. This zone is also characterized by having a low rate of proliferation and proteoglycan and collagen type IIB synthesis. The grove of Ranvieer is surrounding this zone (4).
The role of the resting zone in endochondral ossification:
There is an existing possible hypothesis that the resting zone contains chondrocytes (stem cell like cells) which acts as progenitor cells that are able to give rise to chondrocytes that are characterized by having rapid division. Each clone will constitute a cell column that is aligned parallel to the long axis of the bone. When the cells undergo replication, and inorder to keep the columner organization, the two daughters line up parallel to the long axis