Flashcards
Ion Channels
Cards in this deck (9)
- 1What stimuli are known to gate regulated ion-channels?• Voltage
• Ligand
• Stretch or Pressure
• Light - 2What techniques can we use in order to study single channel properties?• Patch clamp technique
• Planar Lipid Bilayer - 3What parameter can we measure from a single channel recording?• Open probablity
• Mean open times
• Mean closed times
• Conductance - 4What can these parameters tell us about the properties of ion channels?• What opens the channel
• What the channels conductance is
• What the channel is selective for
• The effect of drugs on the channels function/pharmacology of the channel - 5Define Ohms lawV(voltage) = I(current) X R(resistance)
- 6Explain how you would experimentally obtain the necessary information in order to calculate the single-channel conductance for a given ion?Under voltage-clamp conditions we can measure the single channel current amplitude at a given voltage. We can then construct a current-voltage relationship. The slope of the current-voltage relationship gives us the conductance.
- 7How do you calculate conductance from a data set, of current & respective voltage?3Conductance is the inverse of resistance (1/R) --> calculate the gradient of the current- voltage (I-V plot) relationship (I/V=1/R).
Unit of conductance: Siemens (S = 1/ohm) - 8What is conductance a measure of?How 'good' a channel is at letting current through
- 9Why is it important to study the basic biophysical properties of an ion channel?Single channel properties are unique for a given ion channel and this enables us to functionally identify the channel
Important when we want to look at the action of a drug or the effect of a single point mutation which may underlie a given pathology as a result of altered channel function
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- MD2001 Flashcards on Ion Channels, created by Lareyna Mcmenemy on 27/07/2018.
- Created by
- Lareyna Mcmenemy · Jul 2018
- Updated
- Jul 27, 2018
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