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Li2012 Calcium mediated synaptic plasticity

ABSTRACT: Li2012 Calcium mediated synaptic plasticity This model is an extension of BIOMD0000000183. This model is described in the article: Calcium input frequency, duration and amplitude differentially modulate the relative activation of calcineurin and CaMKII. Li L, Stefan MI, Le Novère N. PLoS ONE 2012; 7(9): e43810 Abstract: NMDA receptor dependent long-term potentiation (LTP) and long-term depression (LTD) are two prominent forms of synaptic plasticity, both of which are triggered by post-synaptic calcium elevation. To understand how calcium selectively stimulates two opposing processes, we developed a detailed computational model and performed simulations with different calcium input frequencies, amplitudes, and durations. We show that with a total amount of calcium ions kept constant, high frequencies of calcium pulses stimulate calmodulin more efficiently. Calcium input activates both calcineurin and Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) at all frequencies, but increased frequencies shift the relative activation from calcineurin to CaMKII. Irrespective of amplitude and duration of the inputs, the total amount of calcium ions injected adjusts the sensitivity of the system to calcium input frequencies. At a given frequency, the quantity of CaMKII activated is proportional to the total amount of calcium. Thus, an input of a small amount of calcium at high frequencies can induce the same activation of CaMKII as a larger amount, at lower frequencies. Finally, the extent of activation of CaMKII signals with high calcium frequency is further controlled by other factors, including the availability of calmodulin, and by the potency of phosphatase inhibitors. This model is hosted on BioModels Database and identified by: BIOMD0000000628. To cite BioModels Database, please use: BioModels Database: An enhanced, curated and annotated resource for published quantitative kinetic models. To the extent possible under law, all copyright and related or neighbouring rights to this encoded model have been dedicated to the public domain worldwide. Please refer to CC0 Public Domain Dedication for more information.

SUBMITTER: Varun Kothamachu

PROVIDER: BIOMD0000000628 | BioModels | 2024-09-02

REPOSITORIES: BioModels

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			Action	DRS
	BIOMD0000000628?filename=BIOMD0000000628-biopax2.owl	Owl
	BIOMD0000000628?filename=BIOMD0000000628-biopax3.owl	Owl
	BIOMD0000000628?filename=BIOMD0000000628-matlab.m	Other
	BIOMD0000000628?filename=BIOMD0000000628.m	Other
	BIOMD0000000628?filename=BIOMD0000000628.ode	Other

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Publications

Calcium input frequency, duration and amplitude differentially modulate the relative activation of calcineurin and CaMKII.

Li Lu L Stefan Melanie I MI Le Novère Nicolas N

PloS one 20120904 9

NMDA receptor dependent long-term potentiation (LTP) and long-term depression (LTD) are two prominent forms of synaptic plasticity, both of which are triggered by post-synaptic calcium elevation. To understand how calcium selectively stimulates two opposing processes, we developed a detailed computational model and performed simulations with different calcium input frequencies, amplitudes, and durations. We show that with a total amount of calcium ions kept constant, high frequencies of calcium ...[more]

PMID: 22962589

Publication: 1/8

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