AMPA receptors synaptic distribution

NMDARs are relatively stable components of the postsynaptic membrane. For example, the basal rate of endocytosis of surface AMPA receptors in cultured cortical neurons is nearly threefold that of NMDARs (20,117). Thus, it is not surprising that synaptic plasticity is linked more to changes in numbers and distribution of surface AMPA receptors than it is to NMDARs consequently, studies on glutamate receptor internalization have focused more on AMPA receptors than on NMDARs. 

Kharazia VN, Weinberg RJ (1997) Tangential synaptic distribution of NMDA and AMPA receptors in rat neocortex. Neurosci Lett 258 41-44. 

Fig. 48. Electron micrograph of the synaptic distribution of immunoreactivity for the GluRl subunit of the AMPA receptor in rat cerebellum as detected by an antibody against the carboxy-terminal (intracellular) region of GluRl. A. A spine (s) emerging from a Purkinje cell dendrite (Pd) establishes an immunopositive type 1 synapse (solid arrows) with a parallel fiber terminal (pft). Intra-cellular immunoreactivity is present inside Bergmann glial cell processes along dendritic elements (e.g., open arrow). B. The peroxidase reaction end-product labels the postsynaptic density (psd) at the intracellular face of the postsynaptic membrane (pom) and not the synaptic cleft between the presyaptic (pem) and postsynaptic (pom) membranes. Scale bars in A = 0.5 /xm, in B = 0.1 jum. Baude et al. (1994).

---