4-35 Connective tissue

DENSE REGULAR CONNECTIVE TISSUE – 1

Many organs are covered by a capsule that holds their constituents together and protects them from mechanical pressure and from direct contact to neighbor organs. This is the case, for example, of salivary glands, organs in the abdominal cavity such as the liver, spleen, and adrenal glands, and also lymph nodes scattered throughout the connective tissue of the body, surrounded by adipose tissue or loose connective tissue.

The capsules are composed by a layer of dense, modeled (or regular) connective tissue. Unlike the collagen fibers of the luoos and the irregulat connective tissue its collagen fibers re organized im parallel to each other. In consequence, it is stronger and more resistant to mechanical forces than the dense irregular connective tissue, whose collagen fibers are arranged in numerous directions. The fibers of In capsules are placed in parallel to the surface of the organs they cover. There are relatively few cells in this tissue, mostly fibroblasts.

The figure shows a small segment of the capsule that encloses a testicle (highlighted in blue). The fibroblasts and fibrocytes of this type of tissue are arranged in parallel to the collagen fibers. Their nuclei are often very thin.