MCQ Flashcards
D: 100% bioavailability is by definition achieved by:
intravenous
A:The neurotransmitters in the autonomous nervous system are
Acetylcholine + noradrenaline
P: A true competitive antagonist …
binds to the same site as an agonist but does not cause a conformational change that can activate the receptor
C: Which central acting drugs as central stimulative?
Analeptics
C: Which is a pre-condition for central action of a drug?
Lipophobic properties
Passage through the BBB and interaction with central structures like receptors
Increasing Adrenaline levels significantly
lowering memb potential
Boosting GABAergic function
Passage through the BBB and interaction with central structures like receptors
A: In the autonomous nervous system nicotine is
1) Dose-dependently an agonist and a blocker at the nicotinergic ganglia
2) Just an agonist without effects
3) An agonist at muscarinergic R
4) An agonist at ganglia, but a blocker at NMJ
Dose-dependently an agonist and a blocker at the nicotinergic ganglia
(Nicotine binds to Ach receptors)
B:What energy sources do plasma membrane transporters of neurotransmitters mainly use?
Na+ gradient across the membrane
B:What are the differences between plasma membrane transporters and vesicular transporters for neurotransmitters?
Plasma membrane transporters use the Na+ gradient to clear the synaptic cleft of the released neurotransmitter. Vesicular transporters use (among others) a pH gradient to pump neurotransmitter molecules into synaptic vesicles.
C:Which class does not belong to the antidepressants? SSRI Monoamine Oxidase Inhibitors Psychostimulants Butyrophenones Non-selective NA-5HT reuptake inhibitors
Butyrophenones
P:An ideal agonist will
shift the ratio in favor of the active state
P: Randomisation
removes sources of bias, even those that are not known
B: Neurotransmitter activity can be terminated by:
Enzymatic inactivation, diffusion and uptake
B: Which of the following statement(s) is/are correct?
Glutamate is synthesized in the soma and packed into vesicles which are transported to the synapse. The source of Glutamate is Tyrosine, which is decarboxylated and than aromatized by specific enzymes in the trans-Golgi network.
Neurons don’t synthesize Glutamate at all, but depend entirely on supply by Glial cells
Glutamate concentration in the cerebrospinal fluid is high and it can be taken up directly
There are 2 main sources for Glutamate, -ketoglutarate taken from the Krebs-cycle and Glutamine, which is partially delivered by glia cells.
Glutamate is an essential amino acid, it has to be included in the diet and is taken up directly into the blood stream which delivers it through the blood brain barrier to the brain.
There are 2 main sources for Glutamate, -ketoglutarate taken from the Krebs-cycle and Glutamine, which is partially delivered by glia cells.
P: Which of these statements about the Schild Method is false?
The Schild method requires binding to be at equilibrium.
The Schild method cannot estimate the number of binding sites in a receptor.
The Schild method provides a microscopically correct estimate of the binding affinity of a competitive antagonist.
The Schild method is appropriate for ligand gated ion channels, but not for metabotropic receptors.
The affinity of the agonist used does not affect the antagonist KB determined by Schild’s method.
The Schild method requires binding to be at equilibrium.
The Schild method cannot estimate the number of binding sites in a receptor.
The Schild method provides a microscopically correct estimate of the binding affinity of a competitive antagonist.
-> The Schild method is appropriate for ligand gated ion channels, but not for metabotropic receptors.
The affinity of the agonist used does not affect the antagonist KB determined by Schild’s method.
C: Benzodiazepines do not
Induce Cognitive Improvement But does Influence GABAergic function Have antiepileptic effects Have a wide therapeutic range Reduce anxiety
P: Which of these statements about agonists is correct?
Full agonists evoke stronger responses than partial agonists
P: Which of these statements about ligands is correct?
Antagonists do not change the response of a receptor.
P: Computational drug design
allows the identification of promising novel therapeutic agents that can be refined with other methods.
Not true:
- only works if you want to design lipophilic molecules.
- cannot be used to design a drug that passes BBB
A: Muscle relaxants do not
- act as agonist @NMJ
- depolarize memb
- relax skeletal muscle
- induce anaesthesia
- have adverse drug effects
Induce anaesthesia
C: Dopaminergic drugs in Parkinsons disease do not
Promote dopamine synthesis
Decrease Ach levels by competitive mechanisms
Prevent DA degradation
Promote DA release
Act as receptor agonists at D2-R alone
Decrease Ach levels by competitive mechanisms
B: Which of the following statement(s) is/are correct? About GABA synthesis
GABA is synthesized directly from Glutamate via Glutamatedecarboxylases. Two Isoforms of this enzyme exist, GAD65 and GAD67
A: An indirectly acting parasympathomimetic drug acts
1) blocking Ach release
2) selective at muscarinergic R
3) Increasing acetycholine levels in the synaptic cleft
4) Lowering adrenaline levels significantly
5) Boosting GABAergic function
Increasing acetycholine levels in the synaptic cleft
P: A partial agonist will
fix the ratio of inactive to active receptor at a given, agonist specific value, regardless of its concentration
A: Beta-2-sympathomimetic drugs do not
1) Have an anabolic effect
2) Used as tocolytics
3) Dilate arterioles
4) Decrease heart rate
5) Cause bronchodilation
4)Decrease heart rate
P: Glutamate receptors are amongst the best understood receptors in terms of mechanisms of activation because
1) numerous co-crystals of the ligand binding domain with a range of agonists and antagonists have been published
2) the crystal structure of the full length receptor revealed a single Glutamate binding site
3) glutamate acts at only one class od receptors, making it easy to work out all the details
4) each subtype is only expressed in a few cells in the brain
5) they are surprisingly simple molecules, consisting of only a single transmembrane helix
numerous co-crystals of the ligand binding domain with a range of agonists and antagonists have been published
