Twelve pregnant rabbits at the stage of the 9th-day-post-coitus were studied on the change of the blood vessel in the endometrium, by means of the scanning electron microscopy with the resin casts. The development of the subepithelial capillary plexus was shown in the placental fold forming a well-defined capillary complex. The surface capillaries comprising the plexus were noted, and some of them showed a change into the small blood sinuses. A number of fine bud-like protrusions or surface irregularities was defined in the capillaries in the region adjacent to the placental fold. Probably they represent minute aneurysm, blood sinus formation or capillary hemorrhage.
The H-active heptasaccharide showed nearly the same chromatographic mobility with lacto-N-neotetraose after the liberation of fucosyl, galactosyl and N-acetylglucosaminyl residues by the enzyme actions. The A-active octasaccharide liberated N-acetyl-galactosamine by the enzyme from pig liver, thus abolishing its A activity and instead manifesting H activity. After the liberation of N-acetylgalactosaminyl residue, it gave the same RLNT with that of H-active heptasaccharide. The B-active octasaccharide lost B activity through the liberation of galactose and manifested H activity by α-(1→3)-D-galactosidase from Cl. Sporogenes Maebashi. After the liberation of galactosyl residue, it gave the same RLNT with that of H-active heptasaccharide.
Procollagen, a precursor of collagen, was isolated from cultured medium of matrix-free cells from tendon of 16-day-old chick embryos. Tendon procollagen was shown, by limited proteolysis with pepsin followed by gel chromatography, to possess collagenase inhibiting capacity at its N- and/or C-terminal additional peptide portion(s). The results suggest that collagenase inhibiting activity is manifested upon conversion of procollagen to collagen to protect it from proteolysis with collagenase.