Reticular Connective Tissue

Reticular connective tissue is another name for reticular fiber which is an essential part of a tissue structure. The cells that build up as reticular fibers are the fibroblasts which are also known as reticular cells. Reticular fibers are made of collagen and glycoprotein. They are very thin and are almost invisible in histological sections. However, they can be viewed microscopically after impregnation with silver stains. This affinity of reticular fiber for silver stain is known as argyrophilia. They are also impregnated with PAS reaction because of glycoprotein present in it. Reticular fibers are also a form of collagen type III.

The tissues arrange themselves for cells in various organs like bone marrow, lymph nodes, spleen and liver. These tissues have a peculiar feature, they never exist alone rather you will always find reticular cells and fibers with other cells. Reticular fibers are the part of most of the connective tissues and have always been the dominant fiber. This tissue forms a structural framework for organ cells in many organs and tissues.

Structure of the Tissue

When the tissues are viewed closely, they are found to be in series of branching threads. Reticular fibers present in reticular tissues are very fragile and come together to form a mesh work. To get a microscopic view of these cells, special stains are used because they are not easily viewed even in microscopes. For example, when silver stains are used in histological sections, reticular fibers appear like black threads and the coarse collagen fibers look reddish-brown. The reticular fibers are assumed to be different from collagen fibers due to various staining characteristics. The tissue structure looks very similar to that of elastic connective tissue. The only difference is that the collagen fibers are branched in reticular tissues whereas they lie parallel in elastic tissues. The structural framework of collagen lattice in this tissue is such that it provides great strength and support to the organs of human body system.

Similar to other tissues in the body, it also breakdown and are recycled and replaced by new and active tissues. The cells are destroyed when they stop functioning and immediately new strands of collagen are generated to replace the damaged cell. The task of formation of new reticular fibers and maintenance of the existing ones is handled by some specialized cells.

Functions of the Tissue

The most important function of this tissue is to provide support to the organs, tissues and individual cells like adipose tissues and muscles. It forms a dense tissue structure and holds together the cells of smooth muscle tissue and also helps in the formation of basement membrane. The mesh network formed by the reticular fibers is useful for those organs and tissues in which the cell movement and diffusion are the important functions. It forms a supporting wall for blood vessels and a strong network for other cells, skeletal and nerve fibers. It also performs the function of filter in organs like spleen and lymph nodes.

Now let's understand the functioning of the tissue by relating it to an organ. Reticular fibers support the cells of the liver. They are visible when impregnated with silver stain preparation. The reticular fiber support each individual sheet of the liver cell (hepatocytes) and reticular connective tissues are the only supporting tissues available. While supporting the liver cell, the network enables the exchange of content between the hepatocytes and blood.

So, after understanding the structure and functions of the tissues, we can see its vital role played in the smooth functioning of the various organs.