Receptors Flashcards
What does intrinsic activity mean?
The drug binds to the receptor but it doesn’t activate it.
What is the difference between a competitive and non-competitive antagonist?
Competitive - binds to the same receptor site as the agonist.
Non-competitive - binds to a different site
How can the effect of a competitive antagonist be overcome?
By increasing the concentration of agonist.
Emax is a measure of what?
Efficacy.
What is pA2?
The negative logarithm of the molar concentration of antagonist that produces an agonist does ratio of 2.
What is the primary inhibitory neurotransmitter in the CNS?
GABA
What type of receptor is the GABAa receptor?
Ligand-gated ion channel receptor.
What are benzodiazepines used for?
Treating anxiety, e.g. diazepam.
How do benzodiazepines increase the inhibitory effect of GABA?
- By increasing the affinity of the receptor for GABA
2. The frequency of ion channel opening
What is receptor supersensitivity?
Increase in receptor number.
What is responsible for myelinating axons in the CNS?
Oligodendrocytes
What is a neuromuscular junction?
A synaptic connection between a motor nerve and skeletal muscle.
What are the receptors for acetylcholine?
Nicotinic acetylcholine receptors (ligand-gated ion channel receptors)
Noradrenaline is released from every post-ganglion in nerve fibre except for?
The sweat glands - they release adrenaline.
Which receptors are activated to cause pupil constriction in the eye as a parasympathetic response?
M3 muscarinic receptors
