Ultrastructural alterations in glycosaminoglycans of dog femoral condylar cartilage after surgical division of an anterior cruciate ligament: a study with cupromeronic blue in a critical electrolyte concentration technique
Orford, C.R.; Gardner, D.L.; O'Connor, P.; Bates, G.; Swallow, J.J.; Brito-Babapulle, L.A.
Journal of Anatomy 148: 233-244
1986
ISSN/ISBN: 0021-8782 PMID: 3693089 Document Number: 276535
The leaf stifle joints of twelve male and female beagle dogs from a closed colony were subjected to aseptic surgical division of the anterior cruciate ligament. The left stifle joints of 6 animals were subject to a sham operation. All the right stifle joints and the joints of 6 further normal control animals were untouched. One, 12, 16, 24, 32 and 64 weeks after surgery, blocks of central femoral condylar cartilage were collected a) into buffered glutaraldehyde (glut) and osmic acid before staining with heavy metals for conventional electron microscopy or b) into buffered solutions of cupromeronic blue in glut and magnesium chloride, at 0.025 M or 0.3 M, to demonstrate all tissue anions or sulphated glycosaminoglycans (GAG) respectively. The results demonstate that cruciate ligament section causes a syncvitis and rapid changes in cartilage structure. An amorphous material appears at the articular surface: the material is neither GAG, fibrin, hyaluronate, glycoprotein (fibronectin) nor amyloid. Collagen fibril arrays are disrupted, the first evidence of fibrillation. Large, electron-lucent perichondrocytic zones and comparable zones between paired chondrocytes are rich in GAG, an index of new proteoglycan synthesis. The lucent zones do not appear to be regions of collagen degradation. There is an accumulation of GAG-rich matrix on all aspects of superficial, zone I chondrocytes, an alteration from normal canine cartilage structure that is thought to be a chondrocytic response to the mechanical changes imposed by joint instability.