Histological Comparison Of Osteoblasts And Osteoclasts

Histological Comparison Of Osteoblasts And Osteoclasts

Osteoblast and osteoclast.
Answer:

Osteoblast:

Osteoclast:

• Osteoclast Origin:Derived from hemopoietic cells of the monocyte-macrophage lineage.
• Osteoclast Morphology:Multinucleated, large cell.
• Size: 40-100 μm in diameter (approx.).
• Cytoplasm – shows acid phosphatase
• Organelles.
• Extensive mitochondrial, Golgi complex.
• Sparse rough endoplasmic reticulum.
• They occupy a hollow-out depression called Howship’s lacunae.
• Adjacent to the tissue surface, the osteoclast cell membrane shows deep folds called ruffled borders.
• At the periphery of this border, the plasma membrane is apposed closely to the bone surface and the adjacent cytoplasm is devoid of cell organelles.

Osteoclast Functions:

• Resorbs bone by removing the mineralized matrix of bone.
• Regulation:Estrogen – suppresses the production of bone-resorbing cytokines.
• Vitamin D3 – promotes the differentiation of osteoclasts.
• Parathyroid hormone – stimulates the maturation and action of osteoclasts.
• Calcitonin – a potent inhibitor of osteoclast activity.
• TNFα- stimulates differentiation of osteoclast progenitors into osteoclast.