Flashcards in Ligand-Gated Ion Channels & G-Protein Coupled Receptors Deck (95)
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1
Cells communicate with each other using ________ which elicit changes in the ________ of the target cell.
1. Chemical messengers
2. Enzymatic activity
2
Ligand-gated ion channels and G Protein Coupled receptors are found where?
In the plasma membrane of many cells.
3
Membrane receptors are vital for?
Cell to cell communication
4
LGIC and GPCR are sensors for what kind of signals?
Extracellular
5
When signals are transmitted across a membrane by LGIC and GPCR how does the cell respond?
The cell interprets the signal and then the appropriate response occurs.
6
If receptors are like sensors, the signals that they respond to are called ______. If the signal activates the receptor it is an ______. If it inhibits activation of the receptor it is called an _________.
1. Ligand
2. Agonist
3. Antagonist
7
What kind of cells are LGIC and GPCRs found on?
Almost every cell in the body including excitable cells like the ones in nervous system.
8
Action potentials are characteristic of what kind of cells? (name 4).
1. neurons
2. muscle cells
3. cardiac cells
4. some glands
9
Propagation of APs from one cell to another is vital for?
Cell-to-cell communication.
10
The first step in propagation from one cell to another is?
The activation of ligand-gated ion channels
11
Once a LGIC causes a channel to open and the membrane depolarizes, the depolarization activates what? Which results in what?
1. Voltage gated ion channels to open
2. Allows more ions to flow across the membrane and the action potential continues to propagate down the neuron
12
Are LGIC excitatory or inhibitory? What does this mean?
1. They can be either.
2. Meaning that they will either increase the probability or decrease the probability of an action potential in the cell.
13
What dictates whether an ion channel is excitatory or inhibitory?
What kind of ions the channel passes through the membrane.
14
Reducing the difference in charge between a membrane is known as?
Depolarization
15
The flow of negative ions into a cell is known as?
Hyperpolarization
16
The excitatory versus inhibitory classification is true for which types of ion channels/pores?
All of them, not just the LGICs.
17
What is the rate of transmission of LGICs?
Very fast, approx. milliseconds.
18
Agonist binding does what to a LGIC?
Opens the pore
19
Name the two major families of LGICs.
1. Cys-loop receptors
2. Inotropic glutamate receptors.
20
Name three types of cys-loop receptors.
1. nicotinic acetylcholine receptors
2. GABAa receptors
3. glycine receptors
21
Name three types of inotropic glutamate receptors.
1. AMPA receptors
2. NMDA receptors
3. Kainate receptors
22
Inotropic glutamate receptors are receptors that pass ions and are named for the?
Drugs that specifically activate them.
23
What kind of drugs work on cys-loop receptors? (name 5).
1. Nicotine
2. Varenicline (chantix)
3. muscle relaxants (succhs)
4. anti-epileptic drugs
5. anxiolytics.
24
Barbiturates and other anti-epileptic drugs and other drugs used to treat anxiety act how at what receptor?
As agonists on the GABAa receptor (which is a cys-loop)
25
How many subunits does each cys-loop receptor have?
5.
26
Each of the 5 subunits of the cys-loop receptor have how many transmembrane domains?
4.
27
Which of the 4 transmembrane domains in the cys-loop receptor is responsible for forming the ion poor?
2nd.
28
What are the five types of subunits on a cys-loop receptor and what two things do they affect?
1. alpha, beta, gamma, delta and epsilon.
2. They affect how quickly and what types of ions can pass through the receptor.
29
How many alpha subunits does a cys-loop receptor have to have?
2.
30