Modafinil is a wakefulness-promoting agent approved to improve wakefulness in adults who experience excessive sleepiness due to obstructive sleep apnea or shift work sleep disorder. It is used off-label in MS to treat fatigue and sleepiness.
Myelin is a fatty white substance that surrounds the axon dielectric (electrically insulating) material that forms a layer, the myelin sheath, usually around only the axon of a neuron. It is essential for the proper functioning of the nervous system.It is an outgrowth of a type of glial cell.The production of the myelin sheath is called myelination. In humans, myelination begins in the 14th week of fetal development, although little myelin exists in the brain at the time of birth.t is essential for the proper functioning of the nervous system. It is an outgrowth of a type of glial cell. The production of the myelin sheath is called myelination. In humans, myelination begins in the 14th week of fetal development, although little myelin exists in the brain at the time of birth.
Myelin is a collection of lipid fats and proteins that sheaths the long extensions of nerve cells (neurons) called axons. Myelin considerably increases the speed that nerve signals (impulses) move down the axons.he myelin sheath is broken at intervals called the nodes of Ranvier which are rich in sodium channels. This makes the nerve impulses move in a stepwise fashion called salutatory conduction. Myelin is composed of about 80% lipid fats and about 20% proteins.