16. Molecular Pharmacology III

Question 1

Describe Ligand gated ion channels

Answer 1

-Activating a gate opens it up allowing diffusion of ions across the membrane.

-Agonist binds from outside membrane causing a conformational change.

-Select specific ions to flux through ion channel to pass into the membrane.

-Operate on a millisecond time scale are built for high speed signalling.

-Binding of agonist causes a twisting of the binding site causing a conformational change in the transmembrane region opening the gate allowing ions to enter into hydroxyl rich section of the membrane protein allowing them to enter.

Question 2

Describe Tyrosine-kinase Linked receptors

Answer 2

-uses phosphorylation of Tyrosine sites to dimerise subunits which allows signalling platforms to bind that can then send signals.

-activated by extracellular ligand.