part of part of fibroblast tendon cell Tendon cells are specialized elongated fibroblasts that are predominantly found in tendons, the fibrous connective tissue that connects muscle to bone. These cells are biologically unique and essential for the formation and repair of tendons. Tendon cells possess elongated cell bodies and have a spindle or stellate-like shape with thin and long cytoplasmic extensions. They are predominantly positioned longitudinally along the collagen fibers. Their primary function is to produce and maintain the extracellular matrix of tendons, which comprises primarily of collagen, proteoglycans, and other non-collagenous proteins. Tendon cells are actively involved in tendon homeostasis and adaptation to mechanical loading. When tendons are regularly subjected to mechanical strain, these cells react by synthesizing more matrix proteins, thus strengthening the tendon structure. In response to tendon injury or degenerative changes, tendon cells can proliferate and increase their matrix synthesis to repair and regenerate the damaged tissue. However, excessive mechanical loading or aging can result in abnormal responses, leading to pathologic changes in tendon structure and function. In addition, tendon cells also have immunomodulatory functions. They can orchestrate local immune responses by producing a variety of cytokines and chemokines, and by interacting with immune cells that infiltrate the tendon tissue under pathologic conditions. Moreover, tendon cells are capable of expressing genes related to nociception and have a potential role in tendon pain mechanisms. (This extended description was generated by ChatGPT and reviewed by the CellGuide team, who added references, and by the CL editors, who approved it for inclusion in CL. It may contain information that applies only to some subtypes and species, and so should not be considered definitional.) An elongated fibroblast that is part of a tendon. Its cytoplasm is stretched between the collagen fibres of the tendon, and it possesses a central nucleus with a prominent nucleolus. Tendon cell has a well-developed rough endoplasmic reticulum, and it is responsible for the synthesis and turnover of tendon fibres and ground substance. ZFA:0009189 tenocyte https://cellxgene.cziscience.com/cellguide/CL_0000388 muscle attachment cell fibroblast of dense regular elastic tissue tendon