Transporters Flashcards
How many genes for the α subunits are Na+ channels made up of?
10 Genes and 9 are highly similar
Increasing concentration of TTX and STX block what type of channels?
They block wild type channels but not mutant channels
Na+ channels subtype expressions are…
Nav1.1: expressed in CNS (mostly on soma and proximal dendrite)
Nav1.2: Mostly found on unmyelinated axon
Nav1.3: CNS and PNS (Embryonic and early stages)
Nav1.4: skeletal muscle
Nav1.5: mostly in cardiac muscle (TTX-resistant)
Nav1.6: CNS and PNS (node of ranvier)
Nav1.7: PNS, sympathetic neurons, and axons/axon terminal
Nav1.8: PNS (TTX resistant)
Nav1.9: PNS (TTX resistant)
Primary Erythromelalgia (PE) ?
Rare autosomal-dominant condition with spontaneous burning pain of feet and/or hand
- pronounced erythema
- increase skin temp
- mutation in SCN9A (sodium channel alpha subunit)
Ca++ channels pharmacology (HIGH voltage activated channels)
Cav1.1-Cav1.4: L-type channels
Cav2.1: P/Q- type channels
Cav2.2: N-type channels
Cav2.3: R-type channels
Ca++ channels pharmacology (LOW voltage activated channels)
Cav3.1-Cav3.3: T-type channels
Voltage gated K+ channels are made of up?
48 genes in 16 subfamilies Kv or delayed rectifiers: Kv1-12 (including A-type and KCNQ currents) Ca++-activated K+ currents Na+-activated K+ currents CNG and HCN currents KATP currents Twin-pore K+ currents
Delayed Rectifier and K+ channels
Kv channels are main type contributing to membrane Repolarization
Sodium/potassium pump (Na+/k+ ATPase) properties are?
- account for 20-40% of brain energy
- 3 Na+ ions carried out and 2 K+ ions in
- pump is Electrogenic
Cl- flow is regulated by?
Cation-chloride cotransporters
Cl- intracellular level low and high cause?
- Low intracellular level causes hyperpolarization in response to Cl- channel opening
- High causes depolarization due to Cl- channels opening
Development switches
KCC2 renders GABA hyperpolarizing
Disease states can modulate what expression in adult?
KCC2 expression
