Monday, March 20, 2006
Steps to Myelin
Myelin, the fatty insulating coating on many neurons in your brain, is one of those really cool things in biology. That demyelination, or simple lack of myelin, is involved in numerous problems is nothing new, but no one knows really how to address it.
That may be changing: NIH researchers have found that neuronal activity - specifically the electrical impulses that myelin facilitates - seems to stimulate myelination. But there are steps involved. They found that electrical signal transmission causes the active neurons to release ATP (I presume into the extracellular space), where it binds receptors on astrocytes, which in turn release leukemia inhibitory factor (LIF), which stimulates oligodendrocytes to myelinate the active neurons.
It's a pretty classic example of how neuronal survival is linked to activity: the ones involved in a worthwhile pathway will be active, and thus myelinated, those in less useful ones won't be.
That may be changing: NIH researchers have found that neuronal activity - specifically the electrical impulses that myelin facilitates - seems to stimulate myelination. But there are steps involved. They found that electrical signal transmission causes the active neurons to release ATP (I presume into the extracellular space), where it binds receptors on astrocytes, which in turn release leukemia inhibitory factor (LIF), which stimulates oligodendrocytes to myelinate the active neurons.
It's a pretty classic example of how neuronal survival is linked to activity: the ones involved in a worthwhile pathway will be active, and thus myelinated, those in less useful ones won't be.