Hodgkin-Huxley parameters

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thats_karlo

Hodgkin-Huxley parameters

Post by thats_karlo »

Hi everybody!

i'm new student in neuroscince. and i want to know how this software is working,
i read "toturial A" .and i have some questions, could you please explaine me some things;

1- which parameter define membranr resistance Ra?

in toturial A , Ra is defined as axial resistancs and in FAQ (What units does Neuron...)
Ra is cytoplasmic resistance!!

2- How i can change temperatute in HH model?

3- How i can change concentration of ions?

4- How can i change membrane time constant?

5- I know that , HH model inculde Na and K , these ions are resposible for generation one action potential. Could you tell me, How can i test this hypothesis;
incrasing the external calcium concentration will block occurance of the action potential


i will be thankfull if somebodu answer me soon!!!

Regards, KARLO
Last edited by thats_karlo on Thu Sep 08, 2005 8:35 pm, edited 2 times in total.
ted
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Where to start

Post by ted »

thats_karlo

Post by thats_karlo »

Dear ted!

i can not find my answer,

i have looked at a lot of toturials , but i didn't find answer to my question:((

please give short answer to my questions!!!!

THANK'S

C A R L O
ted
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Joined: Wed May 18, 2005 4:50 pm
Location: Yale University School of Medicine
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Post by ted »

OK, short answers.
1- which parameter define membranr resistance Ra?
There is no membrane resistance parameter in NEURON.
Ra isn't membrane resistance, it's cytoplasmic resistivity.
Read the documentation. Start with the papers listed on the Documentation page
at NEURON's web site.
in toturial A , Ra is defined as axial resistancs and in FAQ (What units does Neuron...)
Ra is cytoplasmic resistance!!
So? You just called it membrane resistance. Who do you think is right?
2- How i can change temperatute in HH model?
celsius
Read about it in the Programmer's Reference.
3- How i can change concentration of ions?
Read this
http://www.neuron.yale.edu/neuron/stati ... c.html#ion
and "Expanding NEURON's Repertoire of Mechanisms with NMODL"
Get that from the Documentation page on the web site.
4- How can i change membrane time constant?
Change cm and/or ionic conductances.
How can i test this hypothesis;
incrasing the external calcium concentration will block occurance of the action potential
Create a conceptual model that clearly states how you think calcium affects membrane
properties.
Implement this model in NEURON, and use it in simulations in which you change [Ca]
and observe what happens to excitability.
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