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Consider the pathophysiology of tetany, which is the involuntary contraction of muscles caused by hypocalcemia. From the tetany wikipedia page: Low ionized calcium levels in the extracellular fluid increase the permeability of neuronal membranes to sodium ion, causing a progressive depolarization, which increases the possibility of action potentials. ...


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Caffeine and coffee do not seem to have any significant adverse effect on calcium metabolism. The supposed mechanisms are inhibition of calcium absorption in the intestine and stimulation of calcium excretion in the kidneys. Effects of caffeine on bone and the calcium economy (Food and Chemical Toxicology, Journal, 2002): Caffeine-containing beverage ...


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In short: Calcium can inhibit absorption of iron, but this does not necessary have any significant effect on the long-term iron status in the human body. Iron (Linus Pauling Institute): The presence of calcium decreases iron absorption from both nonheme (i.e., most supplements and food sources other than meat, poultry, and seafood) and heme sources (...


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An earlier source for an estimate of ${[Ca]_{i}}^{+2}$ in spines comes from hippocampal slices of P13-P19 rats (Majewska et al. 2000). The resting ${[Ca]_{i}}^{+2}$ in this paper was ~80 nM and a back-propagating action potential (AP) elicited a response up to ~250 nM (change of ~170 nM). They included $F_{min}$ and $F_{max}$, the minimum and maximum ...


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As far as I know, microscopy (be it with dyes like fluor or with genome-encoded calcium indicators) is really your only good bet, especially for getting quantitative sensitivity, which I think is what you're looking for. Changes in cytosolic calcium are incredibly dynamic both in time and space, which is something to consider when asking how calcium affects ...


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I wish to share an open-source modelling study on Ca2+ oscillations in astrocytes which contains a detailed description of the underlying math and even better, it has supplementary Matlab code published alongside (Zeng et al., 2009). This may be of help to check your formulae and script. Unfortunately I do not feel inclined to start troubleshooting and bug-...


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Short answer Neurotransmitter release is triggered by an influx of calcium ions from the extracellular space into the cytosol through voltage-gated calcium channels in the plasma membrane. Long answer Typical synaptic vesicle release is triggered by calcium influx through T-type calcium channels. These are voltage-sensitive channels in the plasma membrane;...


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Hard water helps in direct and indirect ways. Indirectly, hard water plays an important role in regulation of pH. Respiration and other physiological activities release substances into water that change the water pH and the ions that cause hardness act as buffers and help maintain pH. Directly, they determine the ease with which osmoregulation occurs. The ...


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Parathyroid hormone increases intestinal calcium absorption by increasing production of vitamin D, which in turn uses calbindin. It also enhances calcium reabsorption from the kidney and the release of calcium from bone.


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