MCB 407

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MCB 407 August 30, 2007 Ion Channel
Inactivation Resting Membrane Potential Compartme
nt Model Nernst Equation Goldman
Equation Equivalent Circuit Model Adding
Current and Membrane Capacitance
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Section 1A David Andrew Thursday 5-550 Room
240 LSS Al-awadhi, Saud Badeaux,
Clayton Cardwell, Brian Cox, Laurel Delgado,
Ryan Dutson, Karl Frisby,Jovanca Itsuno,Jaunette L
acy, Marian Mosher, Clayton Panagos,
Melissa Reeves, Christine Underwood,
Alan Workinger, Sarah
Section 1B Nadia Corral-Frias Thursday 5-550
Room 340 LSS Amene, Ikenna Datta, Neha Diaz,
Eduardo Duy, Douglas Edwards, Drew Forbes,
Kathryn Imad, Mays O'Brien, Jesse Ortega,
Michael Pike, Sarah-ann Raybuck, Brendan Sewell,
Jared Shir, Ahmad Torres, Norma Zaninovich, Orel
Section 2A Thabelo Khoboko Friday 3-350 Room
210 Bio West Brown, Jonathan Dave, Ami Feltz,
Jillian Kim, Jennifer Kramer, Joshua Luginbill,
Amy Lovell, Kenneth Martinez, Lindsey Mclaughlin,
Michael Okun, Alec Reavis, Daniel Soap,
Julia Strohen, Monica Thom, Nicole Vermeer,
Adrian Washington, Theron Wiede, Ashley
Section 2B Melinda Mittelman Friday 3-350 Room
240 LSS Caraveo, Jose Clements,
Elizabeth Duarte, Jessica Gibboni,
Robert Kersten, Jillian Kim, Jonathan Malhotra,
Kyle Mitchell, Molly Nagatomo, Kei Ohlson,
Eric Secomb, Clair Shuey, Megan Stombaugh,
David Strobel, Stephanie Sylvester,
Deanna Tonsfeldt, Karen Vomocil, Elisa Wick,
Shanti
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Voltage Gated Ion Channels How are they
Gated? How is their specificity regulated? How
are they Inactivated?
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(No Transcript)
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How Is Inactivation Achieved?
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Fig 6-5
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Kandel 7-1
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Kandel 7-2
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Kandel 7-2
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Kandel 7-2
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Simple Development of a Membrane Potential The
Compartment Model
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Kandel 7-3
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What is the strength of the electrical potential
that develops? The Nernst Equation At
equilibrium, the electrical force is equal and
opposite to the chemical force.
Rearrangement gives Ex RT/zF ln(Xo/Xi)
At 25 degrees, this can be simplified/approximated
to 58/z log (Xo/Xi)
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What about Other Ions?
K An Na Cl Ca
Na Cl K Ca
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In Class Exercise Calculate the Nernst Potential
For The Following Ions
Major Ions in and out of the squid giant axon
Ion In (mM) Out (mM) Equilibrium
potential K 400 20 Na 50 440 Cl- 52 560
Ca 0.1 10 A- 385 0
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Kandel 7-4
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Kandel 7-5
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Driving Force Reversal Potential
Kandel 7-6
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Kandel 7-7
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Goldman Equation Vm RT/F ln (PkKo
PNaNao PClCli)/(PKKiPNaNaiPClClo)
Kandel 7-8
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Kandel 7-9
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Kandel 7-10
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Equivalent Circuit Model of a Neuron
I Na gNa X (Vm-Ena) IK gK X (Vm-EK)
Kandel 7-11
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Vm (ENa x gNa) (EK x gK) (ECl x gCl)/ (gNa
gK gCl)
Kandel 7-12
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Kandel 7-13
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Local Membrane Circuit Properties
Input Resistance
Fig 8-1
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Fig 8-2
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Fig 8-3