Questions tagged [calcium]
22 questions
8
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2 answers
Effect of extremely hard water on marine life?
When researching water quality standards, I found that a minimum and maximum was set for water hardness. Several sources also state that water can in fact be too hard. The question is how does hard water harm marine life? I understand that it is…
J-S
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6
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1 answer
At what calcium concentration does the Sodium-Calcium Exchanger (NCX) "turn on"?
I am interested in the comparison between the Plasma Membrane Calcium ATPase (PMCA) and the Sodium-Calcium Exchanger (NCX) which are two pumps on the plasma membrane of cells that serve to move calcium out of the cell and maintain relatively low…
BioPhysicist
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3
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1 answer
Where do the Ca ions that causes neurotransmitter release from synaptic bouton, come from?
I hope the information you share will help clarify the following doubts and gaps in my knowledge:
Where do the Calcium ions in the influx (which then triggers the neurotransmitter vesicles) come from?
Are they traveling all the way from the ER of…
pulkitsinghal
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3
votes
1 answer
How does coffee cause calcium loss in our body?
Recently on radio a doctor advices to reduce the consumption of coffee as it leads to calcium loss(as my mother described). My initial response was: How could such thing be possible? What kind of experiment have been done to assure that the coffee…
user55350
2
votes
0 answers
What are "inactive" cells during Ca2+ imaging of neurons?
I am reading this paper, and have found the following Figure (Extended Data Figure 5) where they show maps of active cells in the amygdala as imaged with a miniscope and GCaMP6m:
Legend:
Using the spatial filters provided for each neuron by the…
Pugl
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2
votes
2 answers
Turning off the IP3 cascade
After PIP2 has been converted into IP3 and DAG by phospholipase C (PLC), some of the IP3 opens calcium channels in the endoplasmic reticulum and calcium ions can enter the cytoplasm. However, it is unclear to me how this IP3 cascade is terminated.…
Dominique M
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2
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1 answer
Why does hypocalcaemia cause increased muscle contraction?
Calcium is needed for muscle contraction, so how does hypocalcaemia cause increased sustained contraction?
Arun
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2
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0 answers
What is the role of increased cytosolic calcium concentration after firing, in neuronal cell bodies?
I've come across several studies in which scientists were investigating various questions related to neural activity by focusing on neuronal cell bodies using Calcium imaging. As this article suggests for example, cytosolic Ca concentration in the…
Haliaetus
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2
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1 answer
How much does calcium reduce iron absorption?
Generally calcium inhibits the absorption of iron, but to what extent? One atom of calcium will not block 100% of iron absorption, that clearly isn't feasible. On the other hand, if someone ate 10 pounds of calcium, they wouldn't absorb any iron.…
Vane Voe
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2
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Scaling of Ca2+/biochemical signals with dendritic spine size?
I am looking for references that discuss the scaling of biochemical signals in dendritic spines with spine size/synaptic strength. A recent paper (Walker et al. 2017) reports attenuation of NMDA receptor Ca2+ signal with increasing spine size,…
Gaurang
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2
votes
1 answer
Calcium concentration in activated dendritic spines?
What are the typical calcium levels reached in single postsynaptic spines following activation of NMDA receptors by an EPSP or backpropagating spike? Everyone seems to refer to that one Neuron paper (Sabatini et al. 2002) which reports experimental…
Gaurang
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2
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1 answer
Has anyone modelled calcium oscillations using Matlab software?
I have been trying to model calcium oscillations using MatLab, but I cannot obtain the oscillation.
I created a function where I put all the equations and used ode15s to call the function. I have listed the equations and the code.
Can anyone…
nashynash
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2
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What benefit do cardiomyocytes accrue by requiring calcium induced calcium release (relative to skeletal myocytes)?
According to 2 sources I've read, in contrast to skeletal myocytes, cardiac myocytes need calcium to diffuse in to result in contraction. One source says that they need large amounts of calcium to diffuse in through T-tubules as the cardiac…
Robert S
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1
vote
1 answer
Which hormones/factors affect Calcium absorption in the small intestine and its regulation?
I think the question is very broad and cannot find precise mechanisms.
I am not sure about the precise mechanisms of the regulation.
I think they are at least Vitamin D, diffusion and specific calcium channels: calbindins.
More specifically,…
Léo Léopold Hertz 준영
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1
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What causes a tendinopathy to calcify?
I read in this 2012 research paper {1}:
The aetiopathogenesis of CT [calcific tendinopathy] is still controversial, but seems to be the result of an active cell-mediated process and a localized attempt of the tendon to compensate the original…
Franck Dernoncourt
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