Pharmacology

Question 1

What are the 4 types of cell signalling pathways?

Answer 1

Ligand-gated ion channels

G protein coupled receptors

Ligand regulated transmembrane enzymes

Intracellular receptors

Question 2

Describe the ligand gated channel

Answer 2

Found on skeletal muscle

Causes contraction

Pentamer crossing lipid bilayer

Ach binds to a subunit of receptor

Induces conformational change and transient opening of a channel

Na+ flows into cell

Membrane is depolarised and muscle contracts

Question 4

Describe intracellular receptor

Answer 4

Regulates gene expression

Question 5

What are steroids?

Answer 5

Steroids are hydrophobic and pass freely through the plasma membrane

Cytosolic effects of steroids are rapid

Nuclear effects are relatively slow

Question 6

Describe ligand gated transmembrane enzymes

Answer 6

Ligands include insulin and growth factors

Consists of an extracellular binding region and a cytoplasmic enzyme region

Ligands binding results in the receptors binding to each other and their enzyme regions become active

Question 7

What factors affect drug distribution?

Answer 7

Blood flow

Protein binding

Lipid solubility and the degree of ionisation