Does theanine inhibit memory and synaptic...
michaelh 30 Jan 2013
Here ares some qoutes from wiki:
In the regulated pathway, GluR1-containing AMPA receptors are trafficked to the synapse in an activity-dependent manner, stimulated by NMDA receptor activation. Under basal conditions, the regulated pathway is essentially inactive, being transiently activated only upon the induction of long-term potentiation.This pathway is responsible for synaptic strengthening and the initial formation of new memories.
Both GluR1 and GluR2 play an important role in synaptic plasticity. It is now known that the underlying physiological correlate for the increase in EPSP size is a postsynaptic upregulation of AMPARs at the membrane, which is accomplished through the interactions of AMPARs with many cellular proteins.
It inhibits MAPK. MAPK improves synaptic plasticity and memory.
On the flipside, Theanine increases LTP in the ca1 region.
Would homeostasis prevent some of these negative effects?
Edited by michaelh, 30 January 2013 - 10:38 AM.
michaelh 30 Jan 2013
peakplasma 30 Jan 2013
Long-term depression (LTD) is like Schumpeter's Gale - creative destruction. Our brains must clear some dentritic spines so that new ones can emerge and grow. A recent study I posted suggests that LTP is limited without some ratio of LTD.
Also, keep in mind not all Synaptic Plasticity is positive. For example, higher cases of epilepsy in urban populations can be attributed to air pollution-induced LTP.
Edited by peakplasma, 30 January 2013 - 07:20 PM.
michaelh 30 Jan 2013
Theanine has a low, micromolar affinity for AMPA & NMDA antagonism. NMDA blockade has been linked with memory impairment, schizophrenia, cognitive impairment. Also, depression is linked with lower ampa.
It inhibits MAPK. MAPK improves memory.
I would imagine the MAPK, AMPA & NMDA are upregulated after chronic theanine. Meaning theanine actually is positive for memory and cognition.
Edited by michaelh, 30 January 2013 - 07:26 PM.
peakplasma 30 Jan 2013
Theanine has a low, micromolar affinity for AMPA & nmda antagonism? Nmda blockade has been linked with memory impairment, schizophrenia, cognitive impairment and synaptic plasticity inhibition. Also, long term depression is linked with lower ampa.
Theanine has a low, micromolar affinity for AMPA & NMDA antagonism. NMDA blockade has been linked with memory impairment, schizophrenia, cognitive impairment. Also, depression is linked with lower ampa.
Are you talking about long-term depression like being depressed? Or Long-Term Depression (LTD) in the context of synaptic plasticity. By definition, LTD is a relative decrease in AMPA relative to NMDA.
LTP involves the insertion of AMPA receptors at the synaptic membrane. LTD involves removing AMPA receptors from the synapse.The NMDA receptor number remains relatively constant, so it is the ratio of AMPA to NMDA receptors at the synapse that produces LTP or LDP (Lee, 2012)
So AMPA/NMDA antagonism itself is not relevant; what matters is the change in AMPAR relative to the NMDAR and the relative effects of the cascade on each. On top of that you would have to unravel the MAPK cascade and its relative effects.
michaelh 30 Jan 2013
If theanine did have a negative effect, would the body not try and reverse it via homeostasis.
Aside from LTP or LDP, NMDA blockade has been linked with memory impairment, schizophrenia, cognitive impairment. Also, depression is linked with lower AMPA
Edited by michaelh, 30 January 2013 - 10:49 PM.
Joe Cohen 08 Jul 2013
telight 10 Jul 2013
Raptor87 11 Jul 2013
http://www.ncbi.nlm....cles/PMC301012/
BobbyDick 03 Feb 2016
Does LTP make tolerance to positive effects (euphoria, stimulation, better cognition) of drugs (NDRI) and behavioral sensitization (stereotypies)?