คาสิโนไทย NMDAR Extinction in Dendritic Shaft Memory

 

NMDA receptors (NMDARs) are located not only at synapses, but also widely distributed in the extrasynaptic membrane. In particular, the spiny neurons of amygdala, striatum, and cerebral cortex are enriched with extrasynaptic NMDARs to produce คาสิโนไทยNMDA plateaus that are crucial for the generation of action potentials. In the dentate gyrus (DG) of hippocampus, the extrasynaptic NMDARs also make significant contribution to neuronal firing, especially in young granule cells the action potential can be generated by NMDARs alone, without requiring AMPARs (Li et al., 2017). Hence, inhibition of NMDARs in the dendritic shaft can have significant impact on the activation of memory engram cells.

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Figure 15-1. NMDAR extinction in the dendritic shaft. The Ca2+ influx accompanied with the NMDA plateau may cause microtubule depolymerization, producing free tubulin heterodimer which, together with CRMP2, may bind and inhibit NMDARs. This provides a negative feedback to prevent excessive neuronal firing.

It has been well established that Ca2+ ions promote microtubule depolymerization (O'Brien et al., 1997; คาสิโนไทย). Therefore, the elevated Ca2+ concentration accompanied with the NMDA plateau may cause microtubule depolymerization to produce free tubulin heterodimer, which may form the CABT complex with CRMP2, and consequently promoting NMDAR extinction. This provides a negative feedback to prevent excessive neuronal firing.

 

Author: Frank Lee
First Published: October, 2017
Last updated: April, 2018