MCQ

Question 1

D: 100% bioavailability is by definition achieved by:

Answer 1

intravenous

Question 2

A:The neurotransmitters in the autonomous nervous system are

Answer 2

Acetylcholine + noradrenaline

Question 3

P: A true competitive antagonist …

Answer 3

binds to the same site as an agonist but does not cause a conformational change that can activate the receptor

Question 4

C: Which central acting drugs as central stimulative?

Answer 4

Analeptics

Question 5

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

Answer 5

Passage through the BBB and interaction with central structures like receptors

Question 6

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

Answer 6

Dose-dependently an agonist and a blocker at the nicotinergic ganglia
(Nicotine binds to Ach receptors)

Question 7

B:What energy sources do plasma membrane transporters of neurotransmitters mainly use?

Answer 7

Na+ gradient across the membrane

Question 8

B:What are the differences between plasma membrane transporters and vesicular transporters for neurotransmitters?

Answer 8

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.

Question 9

C:Which class does not belong to the antidepressants?
SSRI
Monoamine Oxidase Inhibitors
Psychostimulants
Butyrophenones
Non-selective NA-5HT reuptake inhibitors

Answer 9

Butyrophenones

Question 10

P:An ideal agonist will

Answer 10

shift the ratio in favor of the active state

Question 11

P: Randomisation

Answer 11

removes sources of bias, even those that are not known

Question 12

B: Neurotransmitter activity can be terminated by:

Answer 12

Enzymatic inactivation, diffusion and uptake

Question 13

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.

Answer 13

There are 2 main sources for Glutamate, -ketoglutarate taken from the Krebs-cycle and Glutamine, which is partially delivered by glia cells.

Question 14

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.

Answer 14

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.

Question 15

C: Benzodiazepines do not

Answer 15

Induce Cognitive Improvement
But does
Influence GABAergic function	
Have antiepileptic effects
Have a wide therapeutic range
Reduce anxiety

Question 16

P: Which of these statements about agonists is correct?

Answer 16

Full agonists evoke stronger responses than partial agonists

Question 17

P: Which of these statements about ligands is correct?

Answer 17

Antagonists do not change the response of a receptor.

Question 18

P: Computational drug design

Answer 18

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

Question 19

A: Muscle relaxants do not

• act as agonist @NMJ
• depolarize memb
• relax skeletal muscle
• induce anaesthesia
• have adverse drug effects

Answer 19

Induce anaesthesia

Question 20

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

Answer 20

Decrease Ach levels by competitive mechanisms

Question 21

B: Which of the following statement(s) is/are correct? About GABA synthesis

Answer 21

GABA is synthesized directly from Glutamate via Glutamatedecarboxylases. Two Isoforms of this enzyme exist, GAD65 and GAD67

Question 22

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

Answer 22

Increasing acetycholine levels in the synaptic cleft

Question 23

P: A partial agonist will

Answer 23

fix the ratio of inactive to active receptor at a given, agonist specific value, regardless of its concentration

Question 24

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

Answer 24

4)Decrease heart rate

Question 25

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

Answer 25

numerous co-crystals of the ligand binding domain with a range of agonists and antagonists have been published