What Is an Osteoblastic Response?

Unlike a skyscraper's steel beams, your bones can reshape and repair themselves.

Your skeletal structure may seem permanently fixed, especially if you are an adult. Yet like two sculptors, one removing clay, the other applying it, osteoclasts and osteoblasts never cease reshaping your bones.

Bone

Bone is a connective tissue. Consisting by weight of about one-third collagen matrix (osteoid) and two-thirds mineral, it contains three types of cells---osteoclasts, osteoblasts, and osteocytes, according to the book "Human Physiology, Eighth Edition," by Arthur Vander et al.

Osteoclastic Activity

By secreting hydrogen ions and certain enzymes, osteoclasts dissolve crystals and digest osteoid, breaking down previously formed bone, note Vander et al.

Osteoblastic Response

Stimulated by gravity and muscle tension, osteoblasts respond to osteoclastic activity by laying down new collagen matrix. Once surrounded by calcified matrix, osteoblasts are called osteocytes, observe Vander et al.

Remodeling

Give and take between osteoblasts and osteoclasts constantly replaces old bone tissue with new---a process called remodeling. Reflecting bone's role in providing support, remodeling distributes bone matrix along lines of mechanical stress, according to the book "Principles of Human Anatomy, Ninth Edition," by Gerard Tortora.

Balance

Osteoblasts and osteoclasts maintain a delicate balance. Too much of one over the other can result in bone weakness or malformation, observes Tortora.

References

• "Human Physiology: The Mechanisms of Body Function, Eighth Edition"; Arthur Vander, James Sherman, and Dorothy Luciano; 2001
• "Principles of Human Anatomy, Ninth Edition"; Gerard J. Tortora; 2002

Resources

• Eli Lilly and Company: The Bone Remodeling Process