Popis: |
The subaortic fibrous "ring" in Newfoundland dogs with discrete subaortic stenosis is characterized by the presence of large, uni- and multinucleated, rounded connective tissue cells that resemble chondrocytes in several respects. Connective tissue adjacent to these cells is rich in acid mucopolysaccharides, small but cross-banded collagen fibrils, and small, poorly developed elastic fibers. The chondrocyte-like cells contain numerous cisternae of rough surfaced endoplasmic reticulum and prominent Golgi complexes, and they are surrounded by thick, concentrically arranged layers of basement membrane-like material. The differentiation of cellular and extracellular components of connective tissue in subaortic fibrous rings clearly differs in humans and in dogs with discrete subaortic stenosis. |