Modifications of connective tissue matrices by an enzyme extracted from cartilage

Abstract

The degradative properties of an enzyme extracted from bovine costal cartilage were studied histochemically, autoradiographically, and electronmicroscopically. Previous work had indicated that this enzyme catalyzes the degradation of proteinpolysaccharide, light fraction (PP-L) from bovine costal cartilage to a proteinpolysaccharide with a lower protein content than the original substrate. Attempts were therefore made to ascertain if this protease was species specific and if proteinpolysaccharides other than those present in cartilage were susceptible to enzyme digestion. To this end, the effect of the enzyme on human fetal cartilage and jaws and the epiphyseal plates of neonatal and postnatal rats was studied. Furthermore, 35 S-H 2 SO 4 was injected into pregnant rats, the fetuses were removed and sections of them were digested with the enzyme and then autoradiographed. In the histochemical experiments Alcian Blue with MgCl 2 was used for the staining of tissue polyanions and Bromphenol Blue for the detection of free basic groups. Finally, the limbs of 20 day-old rats were utilized in electronmicroscopic studies.