Connective tissue tendon

Tendons are composed of fibrous connective tissue. Tendon tissue is also formed by the fibroblast ceUs, similar to the way ligaments are formed. These fibroblast ceUs then further differentiate into other specialized ceUs known as fibrocytes. Mature fibrocytes are inactive and compose the ceUular portion of tendons. The function of the tendon is to attach muscles to bones and other parts. 

Gelatin is a protein, made from the hydrolysis of collagen, a protein that makes up about a third of all mammalian tissue. Collagen is a key component of connective tissues, tendons, and bones. 

Skeletal muscle consists of muscle fibers linked together by connective tissue. Tendons and ligaments are composed of collagenous fibers that have a restricted capability to stretch. Tendons connect the muscle to the bone, whereas ligaments connect bone to bone (Fig. 57-1). 

The various cell types are distributed differently within various types of connective tissue fibroblasts often found lying close to collagen fibres, whilst macrophages and mast cells usually appear in clusters around blood vessels. Additionally, whereas fibroblasts are widespread, macrophages are absent from some types of connective tissue, tendons for example. Specialized cells also occur within particular locations for example osteoblasts and osteoclasts (bone), chondrocytes (cartilage), adipocytes (fat tissue) and haemopoietic cells (bone marrow). 

Collagen is a rigid, inextensible fibrous protein that is a principal constituent of connective tissue in animals, including tendons, cartilage, bones, teeth, skin, and blood vessels. The high tensile strength of collagen fibers in these struc-... 

Quite by accident Jennifer discovered that her tendon and connective tissue problems and chronic fatigue were exasperated by molds and chemical exposures. Her understanding is that her various health problems are related to but not completely caused by MCS. One doctor s theory is that her MCS and connective tissue problems may be caused by a metabolic dysfunction. Another doctor, after looking at her extensive medical history, told her she will never find an answer. Jennifer summarizes her ten years of medical tests and examinations by saying that her body doesn t absorb nutrients and her immune system has collapsed. 

Chondroitin sulfates (CS) are ubiquitous components of extracellular matrices of all connective tissues such as the artery and tendon and exhibit a variety of biological functions. They are linear copolymers made up of dimeric units composed of glucuronic acid and N-acetyl galactosamine. The first biological investigation... 

Collagen synthesized in the absence of ascorbic acid (i.e. without hydroxyproline) cannot form its usual stable structure. Collagen is a major component of the structural and connective tissues of the body bone, cartilage, tendons, ligaments, teeth, and skin. Small wonder that things sort of fall apart in the absence of adequate ascorbic acid to support the activity of prolyl hydroxylase. 

Yamauchi M and Katz EP (1993) The post-translational chemistry and molecular packing of mineralizing tendon collagens. Connect Tissue Res 29, 81-98. 

Dense connective tissue This tissue has a large number of fibres. They may be irregularly arranged, as in the dermis, or in sheaths around tendons and nerves, or more regularly organised in the tendons, which link muscles to bones, and in ligaments which connect bone to bone. 

A muscle consists of groups of muscle bundles that join into a tendon at each end. The muscle bundles in the quadriceps are the vastus medialis, rectus femoris, vastus inter-medialis and vastus lateralis. Each bundle is separately wrapped in a sheath of connective tissue. Each muscle is composed of many fibres, packaged into bundles of about... 

In a strap muscle there is little connective tissue within the muscle since most is concentrated in tendons at the end. Such muscles produce the tenderest meat fillet steak is the psoas muscle of a cow. Pennate muscles contain more connective tissue within the muscle itself and hence form the cheaper cuts of meat. 

Muscles are attached to bone by tendons tough, strong strands of connective tissue which transmit the force from muscle to bone. In addition, because of their elastic properties, they convert some kinetic energy into potential energy which is then used during the next stroke. This reduces the amount of ATP and hence the amount of fuel required to power running (Box 13.1). 

Freund, L, Deutsch, M., and Sprecher, A. 1986. Connective-tissue polarity Optical second-harmonic microscopy, crossed-beam summation, and small-angle scattering in rat-tail tendon. Biophys. J. 50 693-712. 

Proteins are the third major class of biomolecules. The word protein comes from the Greek word proteios meaning primary. Protein is the primary material composing cells. Fifty percent of the human body is composed of proteins, and it is estimated that roughly 100,000 different proteins are found in humans. Protein is a major component of structural and connective tissue found in skin, ligaments, bones, muscles, and tendons. Digestive enzymes, insulin, and other hormones are proteins. 

Collagen Like the a-keratins, collagen has evolved to provide strength. It is found in connective tissue such as tendons, cartilage, the organic matrix of bone, and the cornea of the eye. The collagen helix is a unique... 

Our own skin is made up of specialized cells which become filled with microfibrils of keratin as they move outward and become the relatively dry nonliving external surface (Box 8-F). Internal epithelial cells secrete protein and carbohydrate materials that form a thin basement membrane around the exposed parts of the cells. The connective tissue that lies between organs and which also includes tendons, cartilage, and bone consists of a relatively small number of cells surrounded by a "matrix" consisting of the protein fibers collagen and elastin in a "ground substance" rich in proteoglycans (Chapter 4).616 618 in bone, the calcium phosphate is deposited within this matrix. 

COLLAGEN. The major protein component of connective tissue. In mammals, as much as 60% of ihc total body protein is collagen. It comprises most of the organic matter of skin, tendons, bones, and teeth, and occurs as fihrous inclusions in most other body structures. Collagen libers are easily identified on the basis of the following characteristic properties ... 

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