Write a 1 page paper on pharmacology course work. 1. two types of neuroglial cells. Astrocytes and Oligodendrocytes 4 marks 2. two neurotransmitters which are amino acids, and two which are monoamines

Write a 1 page paper on pharmacology course work. 1. two types of neuroglial cells. Astrocytes and Oligodendrocytes 4 marks 2. two neurotransmitters which are amino acids, and two which are

monoamines.

Amino acids:

(i) Glutamate

(ii) Aspartate

Monoamines:

(i) Dopamine

(ii) Adrenaline

8 marks

2. What is an inverse agonist?

Inverse agonists are ligands that like agonists bind to the same active receptors but produce an opposite effect to that of an agonist by stabilize the receptors thereby reducing their activity.

4 marks

4. Which statement is not correct?

a) Benzodiazepines potentiate the action of GABA on GABAA

receptors.

b) Valium sensitises the GABAA receptor to GABA.

c) Benzodiazepines cannot activate GABAA receptors.

d) Barbiturates activate GABAA receptors.

The incorrect statement is _b____ .

2 marks

5. With regard to neurotransmission, what do the letters EPSP stand for?

Excitatory Postsynaptic Potential

2 marks

6. Indicate whether each statement relating to general anaesthetics is true or

false by ticking the appropriate box.

General anaesthetics:

True False

Block sodium channels False

Exhibit potency which correlates with their lipid solubility True

Inhibit excitatory (e.g. glutaminergic) receptors. True

Activate inhibitory (e.g.GABA) receptors True

Hyperpolarise neurones by blocking K+ channels False

5 marks

7. Fill in the blanks below.

Carlsson hypothesized that schizophrenia is the result of excessive

___dopamine____________________ergic transmission in the brain. Consequently, an

example of a “typical” antipsychotic drug is __Perphenazine____________________, which acts by blocking __Dopamine D1 and D2 receptors__________________ receptors (specify the subtype).

6 marks

8. Fill in the blanks below.

Withdrawal (abstinence) symptoms in drug dependency are associated with

reduced ___________dopamine____________ergic transmission in a localised area of

the brain called the ______nucleus accumbens_______________________ otherwise known as “the pleasure centre” of the brain.

4 marks

9. Give three abnormalities most evident in the brains of Alzheimer’s disease

patients, post mortem.

At post mortem Alzheimer’s disease is characterised by neuronal loss, neurofibrillary tangle formation in the neocortex and hippocampus and specific presynaptic markers of cholinergic system appear to the uniformly reduced.

6 marks

10. Briefly describe the role of the Mini Mental State Examination (MMSE),

indicating how the scoring works.

This is a series of questions and tests which is used by clinicians for diagnosing dementia and to assess its severity and progression. If all the answers are correct a maximum score of 30 can be obtained. A score of 27 and above is considered normal while score below that will require further assessment for any mental impairment.

4 marks

11. Define two of the following movement disorders: akathisia, bradykinesia,

dystonia, tardive dyskinesia.

Akathisia is a condition that is characterised by motor restlessness, ranging from anxiety to inability to sit or lie quietly or to sleep. It is a common side effect of neuroleptic medications.

Dystonia is a movement disorder characterized by sustained muscle contractions which results in writing or twisting movements and unusual body postures.

8marks

12. Give two examples of neurotransmitter receptors which are ionotropic

(Class I).

Nicotinic acetylcholine receptors and glutamate receptors

4 marks

13. Name three main classes of glutamate receptor (abbreviations are

acceptable).

The three classes have been named after selective agonists which bind to these receptors such as NMDA, AMPA and KA.

6 marks

14. Complete the table below, filling in all the blanks, giving one example of each

of the five main classes of hallucinogens.

Pharmacological class of

hallucinogen Example:

Anti-cholinergic - Atropine

Catecholamine-like - Mescaline

Serotonin-like - Lysergic acid diethylamide

NMDA antagonists - Selfotel

Opioid kappa agonist - Ketazocine

10 marks

15. Which neural pathway has a role in movement control and is adversely

affected in Parkinson’s disease?

Parkinson’s disease is characterized by profound and selective loss of nigrostriatal dopaminergic neuronal pathway

2 marks

16. a) Name two of the five main types of anxiety disorder.

Generalized anxiety disorder and Obsessive compulsive disorder

4 marks

b) Name two of the four main classes of drugs used to treat such disorders.

Anti-depressants and anti-anxiety drugs

4 marks

17. Name four acute effects of opiates.

Respiratory depression, opiod-induced hyperalgesia, increased mortality and hormone imbalances

8 marks

18. a) What is Schildkraut’s theory of affective disorders?

The catecholamine theory of mood proposed by Schildkraut suggests that depression is associated with a functional deficiency of noradrenaline at receptor sites within the brain and mania is associated with an excess of noradrenaline at central receptor sites.

5 marks

b) Give one example of a second generation anti-depressant drug, indicating

its mode of action.

Bupropion is an example of second generation anti-depressant and its main mechanism of action is known to be dopaminergic and noradrenergic.

4 marks

1. For each neurotransmitter shown below (a - f), select the family to which it

belongs from the following list:

quaternary amine, monoamine (catecholamine), secondary amine

(catecholamine), amino acid (moncarboxylic acid), amino acid (dicarboxylic

acid), polypeptide, opioid pentapeptide.

Neurotransmitter Family

a) Ach - cholinergic neurotransmitter

b) BDNF neurotrophin

c) GABA amino acid (dicarboxylic acid)

d) Glutamate amino acid (monocarboxylic acid)

e) Dopamine monoamine (catecholamine)

f) Met-enkephalin opioid pentapeptide

3 marks

3. For the following passage, delete the incorrect words in the phrases shown in

bold font:

A presynaptic alpha 2 receptor on a serotonergic neuron is called a

heteroreceptor . It reduces

neurotransmitter exocytosis by inhibiting the opening of Ca2+ ion

channels.

3 marks

4. In each case, give one example of:

a) a natural narcotic: ___________opium___________________

b) a semisynthetic opioid: _______hydrocodone_______________________

c) a synthetic opioid: ____________Fentanyl__________________

3 marks

5. With reference to one named neurotransmission mechanism, how does

ethanol mediate its action as a CNS depressant?

Recent studies have shown that depressing effects on the CNS by ethanol is mediated by GABA which is a primary inhibitory neurotransmitter in the CNS. Activation of the GABA receptors by GABA decreases neuronal excitability.

2 marks

9. Which statement is not correct?

a) Valium sensitises the GABAA receptor to GABA.

b) Barbiturates activate GABAA receptors.

c) Benzodiazepines cannot activate GABAA receptors.

d) Benzodiazepines potentiate the action of GABA on GABAA

receptors.

The incorrect statement is __c__ .

1 mark

14. Name three drugs/therapies that are currently in clinical trials (phases 1-3) for

the treatment of Alzheimer’s disease.

AC 1204 for people with mild to modertate disease

Advanced deep brain stimulation of the fornix in people with mild disease

AVP923 for treatment of agitation in Alzheimer’s disease

3 marks

2. Broadly speaking dopamine receptors fall into 2 receptor subtypes. briefly

explain why.

The D1 family of dopamine receptors is coupled to a G protein which activates adenylyl cyclase while the D2 family of dopamine receptors is coupled to a G protein which inhibits adenylyl cyclase.

2 marks

6. Abuse of which substances (state one in each case) might be treated with:

i) mecamylamine _____nicotine antagonist used in smoking cessation programs___________

ii) disulfiram _______used to treat chronic alcoholism by acute sensitivity to alcohol_________

2 marks

7. What is the basis of the dexamethasone suppression test for depression?

The test is used as a measure of the adrenal response to ACTH.

3 marks

8. Give one example of each of the following, indicating in each case the

mechanism of action:

a) a first generation anti-depressant drug.

tricyclic antidepressant: amitriptyline

b) a second generation anti-depressant drug.

Selective serotonin reuptake inhibitors: Fluoxetine

4 marks

10. There are four pharmacological strategies to treat anxiety disorders. Name

two of these, and give one named example of a drug for each.

Selective serotonin reuptake inhibitors: escitalopram

Serotonin and noradrenaline reuptake inhibitors: venlafaxine

4 marks

12. What are the three phases of schizophrenia? Briefly describe the behavioural

symptoms exhibited in each phase.

Prodromal phase : lose interest in usual pursuits, become easily confused, concentration problems, listless, apthetic and a preference to be alone

Active phase: experience, delusions, hallucinations, marked distortions in thinking and disturbance in behaviour and feeling.

Residual phase: people may be listless, concentration problems and general feeling of withdrawal

3 marks

13. Antipsychotic drugs used in the treatment of schizophrenia are split into two

categories. typical and atypical.

a) Give one named example for each category.

Typical antipsychotic drug: Chlorpromazine

Atypical antipsychotic drug: Clozapine

2 marks

b) What is the main problem associated with the use of the typical

antipsychotic drugs?

These drugs carry a high risk of side effects some of which could be very severe.

2 marks

15. The glutamate NMDA receptor is the target of memantine, a drug used in the

treatment of Alzheimer’s disease. How is this receptor implicated in the

pathogenesis of Alzheimer’s disease?

Increased stimulation of the NMDA receptor is implicated in the increased free radical production by which it potentiates the toxicity of several peptides and causes neuronal damage and impairment of synaptic plasticity.

3 marks

16. The following questions refer to the symptoms associated with Parkinson’s

disease (PD).

a) What are the four main motor symptoms of PD and briefly

mention the traits of these symptoms.

They are:

Shaking or tremor that involves involuntary shaking of the arms, legs, hands, jaw or tongue

Slowness of movement which is also referred to as bradykinesia

Stiffness or rigidity of the arms, legs or trunk

Postural instability that involves trouble with balance and possible falls.

4 marks

b) Name two non-motor symptoms associated with PD.

Mood disturbances and apathy and depression are the two symptoms

1 mark

17. What is 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and why has it

been useful in the understanding the pathogenesis of Parkinson’s disease?

MPTP is a model in which the neurotoxin MPTP is employed. This has a competitive advantage over other models as when it causes intoxication it induces a syndrome virtually identical to Parkinson’s disease in humans.