Emerging Link between Alzheimer’s Disease and Homeostatic Synaptic Plasticity

Figure 3

Postsynaptic expression mechanisms in normal and AD synapses. (a) In normal synapses, chronic activity blockade leads to synaptic scaling expressed by a compensatory increase in synaptic AMPAR density and current, whereas chronic activity elevation leads to synaptic downscaling expressed by a compensatory decrease in synaptic AMPAR density and current. (b) In AD, Aβ increases neuronal excitability and/or synaptic activity, leading to induction of synaptic downscaling. Because pathologic feedback loop continues to produce and release Aβ, synaptic downscaling becomes persistent and opposes the postsynaptic expression mechanisms for LTP.

(a)

(b)