Pharmacology: Receptors and Signalling Flashcards
what is autocrine signalling
cell signals to itself
what is paracrine signalling
cell signals to its close neighbours
what is endocrine signalling
blood vessels transport cell’s signalling molecules to distant target cells
what are the 4 main types of receptors
- LGICs
- GPCRs
- kinase-limited receptors
- nuclear receptors
where are LGICs and what are their ligands
- plasma membrane
- hydrophilic signalling molecules, ‘fast’ neurotransmitters
where are GPCRs and what are their ligands
- plasma membrane
- hydrophilic signalling molecules, ‘slow’ neurotransmitters
where are kinase-limited receptors and what are their ligands
- plasma membrane
- hydrophilic protein mediators
where are nuclear receptors and what are their ligands
- intracellular, cytoplams or nucleur membrane
- hydrophobic signalling molecules
what are the 3 things that a ion channel may be gated by
- transmembreane voltage (VGICs)
- chemical signals (ligand)
- physical stimuli (mechanical energy, temp)
what do ion channels do
create a ion conducting transmembrane pore
what do LGICs consist of
several subunits creating a central ion-conducting channel
what can LGICs do
rapidly alter membrane potential
describe what happens when an agonist binds to a LGIC
agonist binds -> rapid conformational change -> ion channel opens -> ions conducted down electrochemical gradient -> cycles back to closed state
what are secondary messenger system
receptor activation modulates an effectors activity
may increase or decrease rate of synthesis of secondary messenger molecules
basic structure of a G protein
- peripheral membrane protein
- 3 subunits - alpha, beta and gamma
- alpha subunit has a binding site for GDP/GTP
