BDNF - brain-derived neurotrophic factor

Professor Bruce McEwen introduces BDNF, a class of neurotrophic molecules released by excitatory neurotransmission and associated with key process and disorders.

BDNF [brain-derived neurotrophic factor] is, of course, one of a class of neurotrophic molecules produced by the brain actually, and also by blood cells and other cells of the body. In the brain, it’s released from neurons when there is excitatory neurotransmission. It has short-term effects on the nervous system; it has also long-term effects – our work and related work suggests that it is a permissive factor for plastic changes in the brain, for either changes in excitability, or in our case, changes in the growth or retraction of dendrites, the generation of synapses, or the retraction of synapses. It’s a facilitator, and it works in collaboration with other agents. For example, I mentioned IGF1 is the circulating hormone that’s taken up from the blood. When you exercise, it helps to stimulate neurogenesis. Well, BDNF also participates in enhancing neurogenesis. We don’t know yet how they work together, if it’s in a linear fashion or if it’s in a converging fashion, because one of the things we know about all the hormones ([e.g.] steroid hormones which I happen to study), is that they work in concert with other agents, both in the brain and coming in outside. So their effects are largely conditional, depending on the activity of other systems.