Psychology Wiki
Register
Advertisement

Assessment | Biopsychology | Comparative | Cognitive | Developmental | Language | Individual differences | Personality | Philosophy | Social |
Methods | Statistics | Clinical | Educational | Industrial | Professional items | World psychology |

Biological: Behavioural genetics · Evolutionary psychology · Neuroanatomy · Neurochemistry · Neuroendocrinology · Neuroscience · Psychoneuroimmunology · Physiological Psychology · Psychopharmacology (Index, Outline)


brain-derived neurotrophic factor
Symbol(s): BDNF
Locus: 11 p14.1
EC number [1]
EntrezGene 627
OMIM 113505
RefSeq NM_170735
UniProt P23560

Brain-derived neurotrophic factor (BDNF) is exactly as it states; a neurotrophic factor found originally in the brain, but also found in the periphery. More specifically, it is a protein which has activity on certain neurons of the central nervous system and the peripheral nervous system; it helps to support the survival of existing neurons, and encourage the growth and differentiation of new neurons and synapses. In the brain, it is active in the hippocampus, cortex, and basal forebrain—areas vital to learning, memory, and higher thinking. BDNF was the second neurotrophic factor to be characterized, after nerve growth factor (NGF) and neurotrophin three (NT-3).

Although the vast majority of neurons in the mammalian brain are formed prenatally, parts of the adult brain retain the ability to grow new neurons from neural stem cells; a process known as neurogenesis. Neurotrophins are chemicals that help to stimulate and control neurogenesis, BDNF being one of the most active. Mice born without the ability to make BDNF suffer developmental defects in the brain and sensory nervous system, and usually die soon after birth, suggesting that BDNF plays an important role in normal neural development.

Despite its name, BDNF is actually found in a range of tissue and cell types, not just the brain. Expression can be seen in the retina, the CNS, motor neurons, the kidneys, the prostate and more.

Effects of stress and BDNF's link in depression[]

Exposure to stress and the stress hormone corticosterone has been shown to decrease the expression of BDNF in rats, and leads to an eventual atrophy of the hippocampus if exposure is persistent. Similar atrophy has been shown to take place in humans suffering from chronic depression.

Main article: Depression and Brain-derived neurotropic factor

Mechanism of action for BDNF[]

BDNF binds at least two receptors on the surface of cells which are capable of responding to this growth factor, TrkB (pronounced "Track B") and the LNGFR (for "low affinity nerve growth factor receptor", also known as p75).

TrkB is a receptor tyrosine kinase (meaning it mediates its actions by causing the addition of phosphate molecules on certain tyrosines in the cell, activating cellular signaling). There are other related Trk receptors, TrkA and TrkC. Also, there are other neurotrophic factors structurally related to BDNF: NGF (for Nerve Growth Factor), NT-3 (for Neurotrophin-3) and NT-4 (for Neurotrophin-4). While TrkB mediates the effects of BDNF, NT-4, and NT-3, TrkA binds and is activated by NGF, and TrkC binds and is activated by NT-3.

The other BDNF receptor, the LNGFR, plays a somewhat less clear role. Some researchers have shown the LNGFR binds and serves as a "sink" for neurotrophins. Cells which express both the LNGFR and the Trk receptors might therefore have a greater activity - since they have a higher "microconcentration" of the neurotrophin. It has also been shown, however, that the LNGFR may signal a cell to die via apoptosis - so therefore cells expressing the LNGFR in the absence of Trk receptors may die rather than live in the presence of a neurotrophin.

Other diseases associated with low BDNF levels[]

Various studies have shown possible links between low levels of BDNF and conditions such as depression, Obsessive-compulsive disorder, Alzheimer's disease, Huntington's disease, Rett syndrome, and dementia, though it is still not known whether these levels represent a cause or a symptom.

Epilepsy[]

Epilepsy has also been linked with polymorphisms in BDNF. Given BDNF's vital role in the development of the landscape of the brain, there is quite a lot of room for influence on the development of neuropathologies from BDNF.

Levels of both BDNF mRNA and BDNF protein are known to be up-regulated in epilepsy. BDNF modulates excitatory and inhibitory synaptic transmission by inhibiting GABAA-receptor mediated post-synaptic currents. This provides a potential reason for the observed up-regulation.

External links[]

Citations[]

  • [2] Targeted disruption of the BDNF gene perturbs brain and sensory neuron development but not motor neuron development.
  • [3] Cell Survival through Trk Neurotrophin Receptors Is Differentially Regulated by Ubiquitination

Memory
Types of memory
Articulatory suppression‎ | Auditory memory | Autobiographical memory | Collective memory | Early memories | Echoic Memory | Eidetic memory | Episodic memory | Episodic-like memory  | Explicit memory  |Exosomatic memory | False memory |Flashbulb memory | Iconic memory | Implicit memory | Institutional memory | Long term memory | Music-related memory | Procedural memory | Prospective memory | Repressed memory | Retrospective memory | Semantic memory | Sensory memory | Short term memory | Spatial memory | State-dependent memory | Tonal memory | Transactive memory | Transsaccadic memory | Verbal memory  | Visual memory  | Visuospatial memory  | Working memory  |
Aspects of memory
Childhood amnesia | Cryptomnesia |Cued recall | Eye-witness testimony | Memory and emotion | Forgetting |Forgetting curve | Free recall | Levels-of-processing effect | Memory consolidation |Memory decay | Memory distrust syndrome |Memory inhibition | Memory and smell | Memory for the future | Memory loss | Memory optimization | Memory trace | Mnemonic | Memory biases  | Modality effect | Tip of the tongue | Lethologica | Memory loss |Priming | Primacy effect | Reconstruction | Proactive interference | Prompting | Recency effect | Recall (learning) | Recognition (learning) | Reminiscence | Retention | Retroactive interference | Serial position effect | Serial recall | Source amnesia |
Memory theory
Atkinson-Shiffrin | Baddeley | CLARION | Decay theory | Dual-coding theory | Interference theory |Memory consolidation | Memory encoding | Memory-prediction framework | Forgetting | Recall | Recognition |
Mnemonics
Method of loci | Mnemonic room system | Mnemonic dominic system | Mnemonic learning | Mnemonic link system |Mnemonic major system | Mnemonic peg system | [[]] |[[]] |
Neuroanatomy of memory
Amygdala | Hippocampus | prefrontal cortex  | Neurobiology of working memory | Neurophysiology of memory | Rhinal cortex | Synapses |[[]] |
Neurochemistry of memory
Glutamatergic system  | of short term memory | [[]] |[[]] | [[]] | [[]] | [[]] | [[]] |[[]] |
Developmental aspects of memory
Prenatal memory | |Childhood memory | Memory and aging | [[]] | [[]] |
Memory in clinical settings
Alcohol amnestic disorder | Amnesia | Dissociative fugue | False memory syndrome | False memory | Hyperthymesia | Memory and aging | Memory disorders | Memory distrust syndrome  Repressed memory  Traumatic memory |
Retention measures
Benton | CAMPROMPT | Implicit memory testing | Indirect tests of memory | MAS | Memory tests for children | MERMER | Rey-15 | Rivermead | TOMM | Wechsler | WMT | WRAML2 |
Treating memory problems
CBT | EMDR | Psychotherapy | Recovered memory therapy |Reminiscence therapy | Memory clinic | Memory training | Rewind technique |
Prominant workers in memory|-
Baddeley | Broadbent |Ebbinghaus  | Kandel |McGaugh | Schacter  | Treisman | Tulving  |
Philosophy and historical views of memory
Aristotle | [[]] |[[]] |[[]] |[[]] | [[]] | [[]] | [[]] |
Miscellaneous
Journals | Learning, Memory, and Cognition |Journal of Memory and Language |Memory |Memory and Cognition | [[]] | [[]] | [[]] |



|}

Target-derived NGF, BDNF, NT-3

|}

nl:BDNF
This page uses Creative Commons Licensed content from Wikipedia (view authors).
Advertisement