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Flashcards in Growth Factors Deck (10)
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2 Main Functions of Neurotrophins

Increase survival of neurons and regulate formation/maintenance of synapses


4 Ntrophins and Their Rs

NGF binds TrkA
BDNF binds TrkB
NT-3 binds TrkC (also A and B)
NT-4/5 binds TrkB


Major Point about Rs in PNS

Some peripheral neurons/functions depend on one specific Trk, so if you knock out one might lose altogether


p75 R

Initiates cell death if binds Ntrophin or pro-form, or higher affinity for cell survival when complexed w/ Trk


Constitutive Pathway

Usually NGF and developmental, pro-protein matures, cleaved by furin, and targeted to constitutive release vesicles. Carried down postsyn retrograde to cell body to stimulate growth cascades


Regulated Pathway

Usually BDNF and mature, resistant to furin, pro packaged in secretory granules that accumulate at PM for depol release (can be cleaved by pro-prot convertases there or after release). Also transported to axon terminals of producing cell, and helps there? So autocrine or paracrine


3 Mechs BDNF Increases Synaptic Plasticity

Increases # of synapses, conductance of Rs, and expression of Rs


BDNF Val66Met Polymorphism

If Met there instead of Val, working memory is worse, in animals has shown lower BDNF levels


Chronic Stress Peripheral and 3 Central Effects

Increase peripheral levels of NGF, decrease central levels of NGF, BDNF, and NT-3


Aging Effects

Ntrophin Levels same, but Pro levels go up, so maybe p75 causes increased death