Myeliinissa

Myelin is a fatty substance that forms a protective sheath around nerve fibers, which are the long, thin projections of neurons that transmit electrical impulses. This sheath, known as the myelin sheath, is crucial for the efficient and rapid transmission of signals along the nervous system. Myelin is composed of lipids, proteins, and other molecules, and it is produced by a type of glial cell called oligodendrocytes in the central nervous system (CNS) and Schwann cells in the peripheral nervous system (PNS).

The primary function of myelin is to insulate the nerve fibers, allowing electrical impulses to travel more quickly and efficiently. This insulation reduces the amount of energy required to transmit signals and helps to prevent the spread of electrical impulses to adjacent nerve fibers. The myelin sheath is not continuous but is segmented, with gaps called nodes of Ranvier. These nodes are areas where the myelin sheath is absent, and they play a critical role in the saltatory conduction of nerve impulses.

Myelin is essential for various physiological processes, including sensory perception, motor function, and cognitive processes. Dysfunction or damage to myelin can lead to neurological disorders such as multiple sclerosis, Charcot-Marie-Tooth disease, and peripheral neuropathy. Research into myelin and its associated disorders is an active area of study in neuroscience and medicine, with the goal of developing new treatments and therapies to improve the quality of life for individuals affected by these conditions.