Connective tissue function

Korn, J.H., Halushka, P.V. and Le Roy, E.C. (1980). Mononuclear cell modulation of connective tissue function suppression of fibroblast growth by stimulation of endogenous prostaglandin production. J. Clin. Invest. 65, 543-554. 

A further distinction can be made between rapidly acting antirheumatic agents which uncouple and slow-acting ones, such as chloroquine and the corticosteroids which, though not uncouplers, inhibit oxidative processes and may therefore achieve, by a different means, the same interference with anabolic processes essential for connective tissue function. 

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. 

Proteins can be broadly classified into fibrous and globular. Many fibrous proteins serve a stmctural role (11). CC-Keratin has been described. Fibroin, the primary protein in silk, has -sheets packed one on top of another. CoUagen, found in connective tissue, has a triple-hehcal stmcture. Other fibrous proteins have a motile function. Skeletal muscle fibers are made up of thick filaments consisting of the protein myosin, and thin filaments consisting of actin, troponin, and tropomyosin. Muscle contraction is achieved when these filaments sHde past each other. Microtubules and flagellin are proteins responsible for the motion of ciUa and bacterial dageUa. 

In biology, extracellular matrix (ECM) is the extracellular part of animal tissue that usually provides structural support to the cells in addition to performing various other important functions. ECM is the defining feature of connective tissue in animals. ECM includes the interstitial matrix and the basement membrane. 

These disorders are all acquired conditions with no evidence of an hereditary basis. Most of them involve inflammation of the skeletal muscle itself (myositis) (Figure 17), though this may sometimes occur because of initial targeting of the muscle vasculature or connective tissue. Many instances of myositis are classed as idiopathic disorders, in that the precise mechanisms of muscle degeneration are not known, but is widely accepted that these syndromes are associated with abnormal function of the immune system. The syndromes of polymyositis (PM) and derma-... 

Sinusoidal damage from cirrhosis is the most common cause of portal hypertension. The sinusoids are porous vessels within the liver that surround radiating rows of hepatocytes, the basic functional cells of the liver (Fig. 19-2). Progressive destruction of hepatocytes and an increase in fibroblasts and connective tissue surrounding the hepatocytes culminate in cirrhosis. Fibrosis and regenerative nodules of scar tissue... 

Heparin is biosynthesized and stored (probably as a complex with histamine and other basic species) in basophilic granules of mast cells of many animal tissues. (Mast cells, whose function remains largely obscure, are located in connective tissues, near the capillaries, and in the walls of blood vessels.10 28 27)... 

Basophils are the least abundant of the leukocytes and account for less than 1% of the total number of white blood cells. They are similar structurally and functionally to the mast cells found in connective tissues, especially in the lungs, skin, and gastrointestinal tract. Basophils and mast cells play an important role in allergic reactions. The granules of these cells contain many substances, including ... 

Mucosa. The innermost layer of the wall is the mucosa, which consists of a mucous membrane, the lamina propria, and the muscularis mucosa. The mucous membrane provides important protective and absorptive functions for the digestive tract. The nature of the epithelial cells lining the tract varies from one region to the next. Rapidly dividing stem cells continually produce new cells to replace worn out epithelial cells. The average life span of these epithelial cells is only a few days. The lamina propria is a thin middle layer of connective tissue. This region contains the capillaries and small lymphatic vessels that take up the digested nutrient molecules. The muscularis mucosa is a thin layer of smooth muscle. Contraction of this muscle may alter the effective surface area for absorption in the lumen. 

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