Mineralization

Profound stuff from the The Journal of Endocrinology and Metabolism:

"Bone is made in two stages; matrix is formed first and about 2 weeks later (in children) it begins to mineralize; the delay is longer in the adult skeleton. The process of adding mineral to matrix is referred to as "bone mineralization" "

(we know that matrix is composed of a combo of proteins (bone glue) and collagen.)

"It is important this this term not be used for the quite different process of adding bone to the growing skeleton". (This latter statement presumably refers to bone growth from the ephyseal plates.)

Let's sharpen this up a bit:

"Mineralization of bone--essential for its hardness and strength--involves a well orchestrated process in which crystals of calcium phosphate are produced by bone-forming cells and laid down in precise amounts within the bone's fibrous matrix or scaffolding. If the process is not properly regulated, the result can be too little of the mineral or too much....inorganic pyrophosphate is involved in controlling the right rate, the right pace of calcification in the normal skeleton."

and then, from the National Institute of Arthritis:

"Although chemical and physical analyses have revealed many details of the structure and organization of mineral in bone, much remains unclear about the process by which calcium and phosphate ions are sequestered from the soluble phase to form crystals in association with the bone matrix."

"In bone formation, osteoblasts first secrete the proteins of the bone matrix, or osteoid, which acquires mineral after forming as a histologically distinct layer. Several proteins have been identified which the property of inhibiting matrix mineralization, suggesting that the potential for precipitation of mineral is inherent in the physiological milieu, and that a counterbalancing inhibition is required to prevent inappropriate formation of insoluble crystals. ..Yet it remains unclear whether mineralization of bone principally reflects passive chemical processes, requiring only the presence of appropriate local concentrations of the precipitating ions, or instead, involves active biological processes, requiring higher-order functions of cells and their macromolecular components."

How fast mineralization proceeds and also the manner seem important questions.

Training:
Sun. 7/19 Tack work after yesterday's speed work: Rod walk/trot 10 min, about 1/2 each and Art 1.4 miles trot.