Total protein, collagen, nucleic acids and calcium ions during rabbit odontogenesis

Abstract

The accurate quantitation of biochemical patterns during embryogenesis in a specific organ system involves calculating, not merely values for quantities of substrate, but distribution, i.e., concentration per unit tissue space. Embryonic, neonatal and early postnatal tooth germs possess cell populations of unequal size, type and function. Studying a specific molecular species in the “total organ” can be extremely misleading if one assumes the organ system to be homogeneous. The mammalian tooth germ is heterogeneous in most aspects; specifically when considering dynamic alterations associated with development. Therefore, to adjust for some of these factors, this study related morphology to a series of biochemical events. Histological examinations of rabbit deciduous posterior tooth germs representative of the twentieth and twenty-fifth days of gestation, birth, and fifth day postnatal were correlated with chemical parameters. Wet and dry weight determinations indirectly evaluate water content and relationships between intra and extracellular spaces. DNA values establish qualitative values for cell number per tooth germ and related substrate concentration to cell number. Biochemical observations indicated that during initial extracellular organic matrix formation, non-collagenous protein concentrations decreased, whereas collagen and calcium values significantly increased. Since mineralization occurs during latter periods of our experimentation, calcium ion content was related with collagen synthesis and odontogenic extracellular matrices (enamel and dentine). Such base line studies serve as a primary step to understanding mechanisms of differentiation during odontogenesis and suggested stages during development for further research.