Effect of intraarticular injection of chondroitin sulfate into synovial joint elements in an experiment

Abstract

Objective: to study morphological and morphometric changes in the epiphysis bone in a rat during the intra-articular injection of chondroitin sulfate (CS). Mаteriаl аnd methods. The object of the study was the knee joints of 36 Wistar rats. CS injections at a dose of 0.05 ml were performed once a week into one of the knee joints (experimental joint), and isotonic NaCl solution at the same volume was injected into the opposite joint (control joint). The animals in the number of 12 units were withdrawn from the experiment on the 7th, 14th, and 21st days, which corresponded to one week after one-, two-and three-fold intra-articular injections of HC and 0.9 % NaCl. The isolated knee joints were placed in a decalcifying liquid, then were fixed in 10% neutral buffered formalin. 4 micron histological sections were stained with hematoxylin and eosin. The morphometric analysis assessed the thickness of hyaline articular cartilage, the thickness of the epiphysis growth zone cartilage, and the cell content of the subchondral bone. Results. The study of the thickness of the articular cartilage, the growth zone of epiphyseal cartilage and the cellular composition of the subchondral bone has showed a statistically significant dynamic increase in these indicators after the 2nd and 3rd intra-articular injections of CS. The assessment of the thickness of the articular cartilage on the 21st day found some statistically significant differences between the experimental and control groups (p < 0.0001), the thickness of the epiphyseal cartilage had increased significantly by that time (p < 0.0001), and the cell content of bone marrow showed statistically significant differences (p = 0.002). Conclusion. The obtained data testify to a pronounced regenerative effect of CS, injected intra-articularly into articular cartilage.