Chondroitin sulfate is one of the important constituents of cartilage, since it is believed by many in the field that this tissue is made up mainly of chondroitin sulfate and the insoluble protein collagen. Chondroitin sulfate is a nonreducing polysaccharide composed of equal parts of an amino sugar and acetic, sulfuric, and glucuronic acids. The sulfuric acid is present in an esterified form. Dziewiatkowski1 showed that administration of radioactive sulfur in the form of sulfate caused a deposition of radioactivity in the knee-joint cartilage of weanling rats. In addition the radioactivity was concentrated in the chondroitin sulfate isolated from the cartilage.
More recently Dziewiatowski2 reported the effect of thiouracil and thyroxine in the deposition of radioactive sulfate sulfur in the knee-joint cartilage of rats. He found that pretreating the animals with thiouracil reduced the uptake of radioactive sulfur in the cartilage of these animals. On the other hand,