Orientation of mineral crystallites and mineral density during skeletal development in mice deficient in tissue nonspecific alkaline phosphatase

摘要: Tissue nonspecific alkaline phosphatase (TNALP) is thought to play an important role in mineralization processes, although its exact working mechanism not known. In the present investigation we have studied mineral crystal characteristics developing skeleton of TNALP-deficient mice. Null mutants (n = 7) and their wild-type littermates were bred killed between 8 22 days after birth. Skeletal tissues processed assess (small angle X-ray scattering, quantitative backscattered electron imaging), analyze bone by light microscopy immunolabeling. The results showed a reduced longitudinal growth strongly delayed epiphyseal ossification null mutants. This was accompanied disturbances pattern, that crystallites orderly aligned with respect axis cortical bone. Among mutants, great variability parameters noticed. Also, immunolabeling osteopontin (OPN) revealed abnormal distribution pattern protein within matrix. Whereas animals OPN predominantly observed cement reversal lines, also randomly dispersed throughout nonmineralized matrix, focal densities. contrast, osteocalcin (OC) comparable both types animals. It concluded ablation TNALP only hypomineralization skeleton, but severe disorder alignment corticalis growing long association disordered matrix architecture, presumably as result impaired remodeling maturation.