Sutural mineralization of rat calvaria characterized by atomic-force microscopy and transmission electron microscopy

Abstract

The application of transmission electron microscopy (TEM) and atomic-force microscopy (AFM) aid the acquisition of detailed structural information on the process of hard tissue formation. The sutural mineralization of rat calvaria is taken as a model for a collagen-related mineralization system. After cryofixation or chemical fixation an anhydrous tissue preparation technique with no staining procedures is used. The atomic-force microscope and the transmission electron microscope are used for structural analysis of the mineralizing region of the sutural tissue. With the application of AFM the collagen macroperiod is shown to be well represented in the unmineralized sutural tissue. At the mineralization front the collagen fibrils are found to be thickened and to change to a characteristic stacked platelet structure. Using TEM the macroperiod is faintly visible before mineral crystallites have formed and is more prominent after the apatite crystallization has started in the fibrils. In this step a needle-like structure of the newly formed apatitic crystals is visible.

Die biologische und medizinische Bedeutung von Calciumphosphaten

“…Unter einem aktiven Prozess versteht man hier die Akkumulation von Calciumphosphat‐Nanokristallen in einem räumlich begrenzten Zellbereich eines Osteoblasten, d. h. in einem Matrixvesikel. Solche Matrixvesikel wurden durch Transmissionselektronenmikroskopie in Frühstadien der Knochen‐ und Zahnmineralisation nachgewiesen 138–140…”

Age-dependent properties and quasi-static strain in the rat sagittal suture

“…Jaslow (1990) used three-point bending and impact tests to determine the bending strength and impact energy absorption of cranial sutures taken from goats ranging from one to nine years of age. Other investigations have used three-point bending tests, uniaxial tension tests, and atomic force microscopy to determine biomechanical properties of pig, rat, and rabbit sutures (Margulies and Thibault, 2000;McLaughlin et al, 2000;Radhakrishnan and Mao, 2004;Tanaka et al, 2000;Wiesmann et al, 1998), but these investigations have been limited to single time points, rather than age ranges. In addition, quasi-static sutural strain has not yet been measured in vivo and the magnitude and behavior of this strain in humans has only recently been calculated theoretically (Henderson et al, 2004).…”

Investigating the ultrastructure of fibrous long spacing collagen by parallel atomic force and transmission electron microscopy

“…Investigating systems with both AFM and TEM has become increasingly prevalent. For example, both techniques have been used in conjunction to examine a number of different biological systems: collagen fibrils,22, 23 proteins,24 protein crystals,25 bacteriophage T4,26 rat liver sinusoidal endothelial cells,27 DNA with bacteriophage phi 29 connector,28 cartilage,29 polysomes,30 rat calvaria,31 and nanotubular structures in pulmonary surfactant 32. Moreover, the use of both techniques in conjunction is very common in the characterization of polymers, nanostructures, and thin films,33–39 and in studies of colloids and clusters 40.…”