Receptors Flashcards
(7 cards)
1
Q
Four major types of receptors
A
Ligand-gated ion channels
G-protein coupled receptors
Catalytic receptors
Nuclear receptors
2
Q
Ligand gated ion channels
ligands
A
Acetylcholine ATP GABA Glutamate Glycine 5-HT
3
Q
Ligand gated ion channels
Nicotinic acetylcholine receptor
A
- Two acetycholine binding sites
- alpha helices forming gate
4
Q
G-protein coupled receptors
A
- N-terminus extracellular
- Seven transmembrane helices
- C-terminus intracellular
Includes muscarinic, adrenergic
5
Q
Catalytic receptors
A
- Extracellular binding domain
- 1 transmembrane helix
- Intracellular catalytic domain
Catalytic (kinase-linked) receptors dimerise when bound to ligand to form the functional receptor
6
Q
Nuclear receptors - class 1 and 2
A
Class I
- present in the cytoplasm
- act as homodimers
- mainly endocrine ligands
- high affinity
Class II
- present in the nucleus
- act as heterodimers
- mainly lipid ligands
- low affinity
7
Q
Speed of receptors
A
Ion channels - fast
G-protein coupled receptors - medium
kinase linked - slow
