Lawrence Prutkin

An ultrastructural study of the effect of hypervitaminosis a acid on the cartilage of the rabbit's ear

Abstract The effects of topically applied vitamin A acid on rabbit ear cartilage were studied at the microscopic level as well as the ultrastructural level. It was observed that vitamin A acid caused a marked loss of the fibrous matrix of the cartilage. The experimentally treated chondrocytes were closely packed together. The cytoplasm contained numerous compact fibres and numerous vacuoles. The normal untreated chondrocytes had few vacuoles. The perichondrium of the vitamin A acid treated cartilage showed very few developing chondrocytes. In contrast, the perichondrium of the control cartilage showed rows of healthy, proliferating chondrocytes. Electron-dense membrane-bound bodies were observed in the matrix. Their morphological similarity to lysosomes is discussed.