Reticular refers to a structure that resembles a net or a network, often characterized by an interlacing pattern of fibers or threads. In biological contexts, the term reticular is commonly used to describe specific structures or formations within tissues and cells.
- R. fibers: They are a type of thin, branching collagen fibers (mainly composed of type III collagen) that form a delicate meshwork in various tissues. They provide a supportive framework for soft organs such as the spleen, lymph nodes, and bone marrow. Reticular fibers are also present in the basement membrane of epithelial tissues and around blood vessels, nerves, and muscle fibers.
- R. connective tissue: This is a specialized type of connective tissue characterized by a network of this kind of fibers and cells. Reticular connective tissue is found primarily in the lymphatic system (e.g., lymph nodes, spleen, and thymus), where it forms a supportive framework for lymphocytes and other immune cells.
- R. formation: It is a complex network of neurons and nerve fibers located in the central core of the brainstem, extending from the medulla oblongata to the midbrain. It plays a crucial role in various physiological processes, including the regulation of sleep and wakefulness, attention, muscle tone, and reflexes.
- R. activating system (RAS): The RAS is a diffuse network of neurons within the reticular formation that is involved in regulating the overall level of consciousness and alertness. It is responsible for the transition between sleep and wakefulness, as well as maintaining attention and alertness during the waking state.
- R. cells: Cells are specialized cells that produce reticular fibers and form the supportive framework of reticular connective tissue. They are found in lymphoid organs such as the lymph nodes, spleen, and thymus, where they help to maintain the structure and function of these tissues.