Lecture 8 Transporters Flashcards
Voltage gated Na+ channels are made up of _____ genes od alpha subunits, ____ are highly similar at amino acid level
10,9
Na+ selectivity is determined by what?
4 amino acids (DEKA). One of which is in each of the 4 pore loop domains.
Increasing concentration of TTX and STX clock current in _______ channels but not _______ channels.
wild-type, mutant
Describe Primary Erythromelalgia (PE) and its mutant gene
Spontaneous burning pain of feet/hands and increased temp
Mutations is SCN9A (sodium channel alpha subunit)
Cav1.1-1.4 is what type of channel?
L type
Cav2.1-2.3 are what types of channels, respectively?
P/Q type, N type and R type
Cav3.1-3.3 are what types of channels?
T type
Cav1s ans Cav2s require ________ changes in voltage
larger
Cav3 requires _______ changes in votlage
smaller
Selectivity is mediated by an __________ in each of the 4 domains
E residue
Name some things that Cav1.1-1.4 are blocked by?
nifedipine, verapamil, diltiazem, green mamba toxin, black mamba toxin
Cav2.1 is blocked by _________, otherwise known as funnel web spider toxin
ω-Agatoxin IVA
Cav2.2 is blocked by _________, otherwise known as cone snail toxin
ω-Conotoxin GVIA
Cav2.3 is blocked by _____ and _________
PLTX-II, SNX-482
Cav3.1-3.3 is blocked by _____, Zarontin and kutoxin
Ni++
Kv channels are main types contributing to _____________.
membrane repolarization.
__________ create and maintain ion gradients
Active transporters
require energy and are slow
Name 3 ion exchangers (they use electrochemical gradients)
Na+/Ca2+
Na/K+/Cl- co transporter
Na+/Cl- co transporter
_____ Na+ ions out, ____ K+ ions in.
3,2
Name 3 things that bind at ATPase pumps
Na+ and K+
STP
Known toxins
Low intracellular Cl- is correct setting for _________ response to opening of Cl- channel
hyperpolarizing
High intracellular Cl- is coorect setting for ________ response to opening of Cl- channel.
depolarizing
Why is it important to regulate intracellular Cl- levels?
Will determine the magnitude and direction of Cl- flow thru ion channels.
What can modulate KCC2 expression in adult and change intracellular Cl-?
disease states
Why will loss of functional expression alter the cellular response to opening of Chloride channels and have a profound impact on neuronal signaling?
B/c NKCC1 is constitutively expressed, which changes KCC2 expression
KCC2 renders ______ ______
GABA, hyperpolarizing
