The magic of ion channels in the neurons

https://i-kh.net/2020/08/26/the-magic-of-ion-channels/

by bucket2015 • 6 years ago

50 21 6 years ago

i-kh.net

failrate• 6 years ago

Link 404

knodi123• 6 years ago

https://i-kh.net/2020/08/26/the-magic-of-ion-channels/

dang• 6 years ago

Thanks! we've changed to that from https://i-kh.net/2020/08/26/how-signals-propagate-through-ne....

fcatus• 6 years ago

Remove the shadow from the website's title.

autisticcurio• 6 years ago

I sometimes wonder if the phrase "they are an egg head" is not so much to do with baldness but more to do with knowledge and intelligence. Phosphatidylcholine (aka Lecithin found in Egg Yolk and elsewhere - 4 egg yolks a day to meet RDA levels) can do wonders for your cell membranes and Vitamin B5 (pantothenic acid) does wonders for your myelin sheaths. I'd be surprised if F1 drivers & fighter pilots werent supplementing above RDA levels with these. Using Potassium Chloride (sometimes called the good salt) helps one to relax in the evening, and sodium chloride as a pick me up in the morning. I wonder if this neuronal ion exchange is anything like the Sodium - Potassium ATPase pump found in other cells as they seem similar. Life is just a complex real-time chemical reaction.

hprotagonist2• 6 years ago

For the Nobel winning work on this from long ago, I heartily recommend:

  Hodgkin, A. L. (1958). The Croonian Lecture: Ionic Movements and Electrical Activity in Giant   Nerve Fibres. Biological Sciences, 148(930), 1–37. Retrieved from http://www.jstor.org/stable/83088

This contains my absolute favorite figure caption ever:

A fresh and lively squid was taken out of the aquarium and immobilized by cutting the nerves connecting the head with the stellate ganglion. The mantle was opened ventrally by a single cut and was spread out under cooled oxygenated sea water in a transparent dish. Using a motor car headlamp to illuminate the animal and a binocular microscope to watch the penetration,...

nextaccountic2• 6 years ago

Poor squid. :(

CamperBob2• 6 years ago

Wir müssen wissen – wir werden wissen. - Epitaph of David Hilbert

We do what we want, because we can. - GLaDOS

Take your pick of rationales, it's not gonna end well for Mr. Squid.

gigama• 6 years ago

Somewhere in the multiverse, a scientifically curious Heptapod takes a fresh and lively humanoid from its terrarium and immobilizes it by cutting the nerves connecting the stellate ganglion...

trhway• 6 years ago

Ender's Game series comes to mind.

james_s_tayler• 6 years ago

Interesting. I knew most of that more or less but didn't know the mechanism by which the myelin sheath speed up the propagation of action potentials but it makes sense.

kkylin• 6 years ago

Hodgkin and Huxley, who figured out how the basic mechanism underlying action potentials, worked on the squid giant axon because it's so large, up to 1.5mm in diameter. And the reason is large is that invertebrates do not have myelin, and the large diameter helps speed up signals:

https://en.wikipedia.org/wiki/Squid_giant_axon

HarryHirsch• 6 years ago

It starts with the telegraph equation. Try this magisterial and slightly obsessive book: https://mitpress.mit.edu/books/cellular-biophysics-2-vol-set

phasetransition• 6 years ago

Interesting. Oliver Heaviside continues his posthumous exploits.

nextaccountic2• 6 years ago

I read somewhere that a significant fraction of the energy budget of the human body is spent on ion pumps (the difference is that ion channels are passive and ion pumps uses energy in form of ATP). That's because keeping an electric potential[1] across the cell membrane drives the mechanism described in this post (and others, like muscle contraction)

Anyway an overview of ion transport mechanisms across the cell membrane is [2]

[1] https://en.wikipedia.org/wiki/Electrochemical_gradient

[2] https://en.wikipedia.org/wiki/Membrane_transport_protein

xattt• 6 years ago

This would explain the 20% (give or take) oxygen requirements of the brain.

wombatmobile• 6 years ago

How might the nervous system have evolved?

Wikipedia says: "Action potentials, which are necessary for neural activity, evolved in single-celled eukaryotes. These use calcium rather than sodium action potentials, but the mechanism was probably adapted into neural electrical signalling in multicellular animals. In some colonial eukaryotes such as Obelia electrical signals do propagate not only through neural nets, but also through epithelial cells in the shared digestive system of the colony."

So, the first "thought" was "hungry, want food"?

And everything we do to get to the 7/11 for snacks is built on that?

rolph• 6 years ago

cells can coordinate by diffusion of signal molecules larger multicellular organisms can use circulatory transport to reduce latency of signals. larger complex organisms coordinate systemic functions with neurons and the electrical signaling between distant parts of the body.

latency is not a good thing to have when you are a motile animal, it limits your overall size and complexity. animal phyla with nervous systems were able to evolve larger bodies avoid being consumed by being too big to eat and became consumers of smaller organisms.

channel-phd• 6 years ago

I’m currently studying ion channels from a biophysical perspective for my PhD. Beyond their fascinating role in neuronal physiology, check out the incredible chemistry and biophysics! A great introduction is MacKinnon’s Nobel lecture: https://www.nobelprize.org/uploads/2018/06/mackinnon-lecture...

jeffybefffy519• 6 years ago

Hate to be the guy to ask this but I like to dig into conspiracy shit like: “5G is bad for our health”.

One of the theories is 4G & 5G cause mess with the electrochemical gradient and voltage gated ion channels. Given you are studying them, whats your opinions on this even being possible?

The magic of ion channels in the neurons

Related Stories