Figure 3.

Ultrastructure features of tenocytes and tenoblasts. The cellular population of tendon is mainly represented by tenocytes: tenocytes are very elongated cells with ovoid and very long nuclei, occupying the entire length of the cell, with a high nucleus-to-cytoplasm ratio. The cellular process are long and thin and in direct contact with extracellular matrix components (A). In the cytoplasm of tenoblasts is often visible a well developed rough endoplasmic reticulum with dilated cisternae (B), few mitochondria, primary and secondary lysosomes, vacuoles, phagosomes and glycogen (C) (O.M. × 3900, ×7900, ×3900).