Lecture 14 - Signalling Molecules And Drug Targets Flashcards
What is the pneumonic for remembering the targets for signalling molecules?
RITE
What does the Pneumonic RITE for signalling molecules stand for?
Receptor
Ion channels
Transporters
Enzymes
What is pneumonic for remembering the subclasses of receptors?
K(L)ING
What does the pneumonic K(L)ING for the subclasses of receptors stand for?
Kinase Linked Receptors
Ion channels (Ligand gated)
Nuclear/intracellular
G-Protein Coupled Receptors
What happens to a Ligand Gated ion channel when a ligand binds to it?
Conformational change
What is the structure of a nAChr?
2a subunits
1B subunit
1gamma subunit
1 delta subunit
How is the ligand gated ion channel nAChr selectively permeable?
Net charge of the pore is negative so doesn’t allow anions through
How does a nAChr change shape when ACh binds to it?
Causes conformational change of the alpha subunits, opens up the kinked chains allowing ions through
What are some Ligand Gated Ion Channels?
nAChr
GABA(a)
Glutamate
Glycine
What is the affect of nAChr on membrane potential?
Excitatory/depolarisation
What is the affect of GABA(a) receptor on membrane potential?
Inhibitory/hyperpolarising
What is the affect of Glutamate receptor on membrane potential?
Excitatory/depolarising
What is the affect of Glycine receptor on membrane potential?
Hyperpolarising/inhibitory
Where are glycine receptors found?
Brain stem and spinal cord
Where are glutamate receptors found?
Major excitatory neurotransmitter in the CNS
Where are GABA(a) receptors found?
Only really found in CNS
Modulate excitatory input by being inhibitory
What agonist can be a short acting depolarising blocker in surgery? (nAChr)
Succinyl choline
What antagonists non depolarising blockers can be used for surgery? (nAChR)
Pancuronium
Vecuronium
What is a major inhibitor receptor in the CNS?
GABA(a)
How many GABAs need to bind to a GABA(a) Receptor?
2
What ion is a GABA(a) receptor permeable to?
Cl-
What is the main family of drugs that target GABA(a) receptors and what do they do?
Benzodiazepines
Keep GABA(a) receptors open allowing lots of Cl- into cell causing hyperpolarisation
What is an anxiolytic?
Something that treats anxiety
What are some drugs that treat anxiety, insomnia or used for sedation?
Benzodiazepines:
-Diazepam
-Aplrazolam
-Clonazepam
What drug can be used for anaesthesia via IV?
Propofol
Very rapid recovery period
What type of ligands bind to Nuclear/Intracellular receptors?
Lipophilic ligands that can pass through the cell membrane
What happens to the activated nuclear receptor once the ligand binds?
Activated receptor binds to DNA to regulate gene expression
What is the name of the DNA sequence which an activated nuclear receptor bind to?
Hormone Response Element
What happens in the AF2 region of DNA when the ligand binds to the HRE (Hormone Response Element) and activates the receptor?
Inhibitory protein lost
What Nuclear receptors are often used as drug targets?
Oral contraceptives act as agonists for oestrogen
Immune suppression after organ transplant
Vitamin A Inflammatory diseases affecting skin (acne treatment)
Vitamins A and D therapy
