7 votes
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Why does hypercalcemia cause muscle weakness, yet hyperkalemia causes muscle excitation?

You're correct about your reasoning for potassium; high extracellular potassium concentration reduces the concentration gradient of potassium across the membrane, pushing the reversal potential for ...
Bryan Krause's user avatar
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3 votes
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Why do V_Na and V_K stay unchanged in Hodgkin-Huxley model?

As you've figured out, the reversal potentials don't change because they're assuming the concentrations don't change. Even relative to $\mathrm{[Na^+]_o}$ and $\mathrm{[K^+]_i}$ the number of ions ...
Bryan Krause's user avatar
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2 votes
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Why is the ordinary cardiac muscle’s target value of the action potential 0mV?

Membrane potentials are determined by the combination of all the membrane-permeable charges, not single ions. You can use the Goldman Equation to calculate the reversal potential for any combination ...
Bryan Krause's user avatar
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2 votes
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Mapping Ion Channel mRNA Copy Number to Channel Conductance

I don't have access to the paper so I can't fully evaluate the relationship you describe. I'm also neither an electrophysiologist nor a However to answer your questions: This to me is a solid "...
Maximilian Press's user avatar
1 vote
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Why don't membrane potentials violate the principle of electroneutrality?

There is perhaps Pauling's principle of electroneutrality "each atom in a stable substance has a charge close to zero" - maybe that's the principle referred to in your book? "Close to&...
Bryan Krause's user avatar
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1 vote

Why is the ordinary cardiac muscle’s target value of the action potential 0mV?

Just for a Comment; I know the Goldman equation (https://en.wikipedia.org/wiki/Goldman%E2%80%93Hodgkin%E2%80%93Katz_flux_equation), and I asked this question because I thought maybe this does not ...
Blue Various's user avatar
1 vote
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Why is there a negative sign before voltage in the gate variable functions of the Hodgkin-Huxley model?

Voltage is a potential difference. Membrane potential is a difference across a membrane. When you calculate a difference A - B or B - A, you get a number that has the same magnitude but opposite sign. ...
Bryan Krause's user avatar
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