Abstract
Calcium carbonate gallstones and calculus-like concrements of calcium carbonate experimentally produced by Maki et al. were cut into thin serial sections by the author's resin-reinforcing technique.1 These specimens were then observed under polarized light, by contact microradioeraphy or after various histochemical stainings. The results obtained were as follows: a) Human calcium carbonate gallstone has a specific structure of its own, though it has been considered until now to be an amorphous mass. b) In human calcium carbonate gallstone, mucopolysaccharides were found evenly distributed, filling the spaces among calcium carbonate crystals in reticular fashion. c) Histochemically, these mucopolysaccharides consisted mainly of sulfated mucopolysaccharides with some contamination of neutral or weakly acid mucopolysaccharides. d) The mucopolysaccharides in human calcium carbonate gallstone are quite similar to sodium alginate in an artificial calculus in their way of distribution and arrangement in minute details. These facts suggest that mucopolysaccharides may take an important part through their bridging action in the formation of calcium carbonate gallstones.
