Lecture 8 Transporters

Question 1

Voltage gated Na+ channels are made up of _____ genes od alpha subunits, ____ are highly similar at amino acid level

Answer 1

10,9

Question 2

Na+ selectivity is determined by what?

Answer 2

4 amino acids (DEKA). One of which is in each of the 4 pore loop domains.

Question 3

Increasing concentration of TTX and STX clock current in _______ channels but not _______ channels.

Answer 3

wild-type, mutant

Question 4

Describe Primary Erythromelalgia (PE) and its mutant gene

Answer 4

Spontaneous burning pain of feet/hands and increased temp

Mutations is SCN9A (sodium channel alpha subunit)

Question 5

Cav1.1-1.4 is what type of channel?

Answer 5

L type

Question 6

Cav2.1-2.3 are what types of channels, respectively?

Answer 6

P/Q type, N type and R type

Question 7

Cav3.1-3.3 are what types of channels?

Answer 7

T type

Question 8

Cav1s ans Cav2s require ________ changes in voltage

Answer 8

larger

Question 9

Cav3 requires _______ changes in votlage

Answer 9

smaller

Question 10

Selectivity is mediated by an __________ in each of the 4 domains

Answer 10

E residue

Question 11

Name some things that Cav1.1-1.4 are blocked by?

Answer 11

nifedipine, verapamil, diltiazem, green mamba toxin, black mamba toxin

Question 12

Cav2.1 is blocked by _________, otherwise known as funnel web spider toxin

Answer 12

ω-Agatoxin IVA

Question 13

Cav2.2 is blocked by _________, otherwise known as cone snail toxin

Answer 13

ω-Conotoxin GVIA

Question 14

Cav2.3 is blocked by _____ and _________

Answer 14

PLTX-II, SNX-482

Question 15

Cav3.1-3.3 is blocked by _____, Zarontin and kutoxin

Answer 15

Ni++

Question 16

Kv channels are main types contributing to _____________.

Answer 16

membrane repolarization.

Question 17

__________ create and maintain ion gradients

Answer 17

Active transporters

require energy and are slow

Question 18

Name 3 ion exchangers (they use electrochemical gradients)

Answer 18

Na+/Ca2+
Na/K+/Cl- co transporter
Na+/Cl- co transporter

Question 19

_____ Na+ ions out, ____ K+ ions in.

Answer 19

3,2

Question 20

Name 3 things that bind at ATPase pumps

Answer 20

Na+ and K+
STP
Known toxins

Question 21

Low intracellular Cl- is correct setting for _________ response to opening of Cl- channel

Answer 21

hyperpolarizing

Question 22

High intracellular Cl- is coorect setting for ________ response to opening of Cl- channel.

Answer 22

depolarizing

Question 23

Why is it important to regulate intracellular Cl- levels?

Answer 23

Will determine the magnitude and direction of Cl- flow thru ion channels.

Question 24

What can modulate KCC2 expression in adult and change intracellular Cl-?

Answer 24

disease states

Question 25

Why will loss of functional expression alter the cellular response to opening of Chloride channels and have a profound impact on neuronal signaling?

Answer 25

B/c NKCC1 is constitutively expressed, which changes KCC2 expression

Question 26

KCC2 renders ______ ______

Answer 26

GABA, hyperpolarizing