BS1060 BLOCK 1- L1

Pharmacology definition

the science of drugs and the science of endogenous compounds

(eg. hormones and neurotransmitters) that act on the same systems

What is a receptor

more specifically to

describe super-families of proteins

Adrenoceptor receptors

Receptors that respond to adrenaline and noradrenaline.

Nicotinic and muscarinic acetylcholine receptors

bind

their endogenous ligand acetylcholine

What are 'Exogenous' ligands

natural compounds (e.g. plant secondary metabolites), or laboratory-

synthesized ligands

What is a ligand

any molecule or ion that binds specifically to a receptor site of another molecule

How is the lipid adapted to binding

The ligand has multiple

points of hydrophobic /

electrostatic / ionic

interactions with the

flexible 3D 'landscape'

of the receptor binding

pocket

(Binds to G proteins) by changing the shape of it

What is ligand binding governed by

Kinetics (rate) of association (K on) and dissociation (k off)

Chattaliea primcible

What is the relationship between ligand concentration and cellular response (x-drug / y-repsponse %)

Linear - positive curve

Semi Log scale - sigmoid

What does ligand potency mean

Effective concentration of ligand producing 50% of Emax response

What is the formula for ligand potency

Ligand affinity + ability to cause a response = potency

What is Radioligand binding

allows quantification of ligand-receptor affinity

Agonists definition

possess both affinity for the receptor and also the

ability to cause receptor activation (intrinsic efficacy) to bring

about a cell response

Antagonists definition

possess affinity for the receptor, but not the

ability to cause receptor activation (i.e. they lack intrinsic

efficacy) and therefore cannot bring about a cell response