Pharmacology

Question 1

Describe what is meant by receptor the basic functions

Answer 1

• Drugs act by interacting with a binding site (receptor)
• cell surface receptors
• intracellular receptors
• ion channels
• carriers
• nuclei acids
• Enzymes

Question 2

Explain the terms agonist and antagonist

Answer 2

Agonist: mimic effect of normal receptor

Antagonist: block action of normal receptor

Question 3

Define affinity and efficacy

Answer 3

• Affinity: chemical attraction of drug to receptor
• efficacy: how good drug is at activating receptor

Question 4

Describe the relationship between agonist concentration and effect

Answer 4

• All have high affinity
  Full agonist ~ high efficacy
  Partial agonist ~ medium efficacy
  Antagonist ~ no efficacy

Question 5

Describe the processes of transmembrane signalling

Question 6

Define the sources for intracellular calcium

Answer 6

• internal stores via IP3
• inhibition of Ca2 transport out of cell

Question 7

therapeutic potential of selective agonists and antagonists

Answer 7

• One signaling molecule may act on several receptor types

Question 8

Structure of cutaneous receptors

Question 9

• Mechanisms of sensory transduction in the skin

Answer 9

• Convergence and divergence

Question 10

Concept of frequency coding

Answer 10

1. A larger stimulus
2. Larger receptor potential
3. Higher frequency of action potentials

Question 11

Structure and function of muscle spindle

Answer 11

• Monitor muscle length and rate of change

(central region lacks myofibrils, gamma motor neurons from CNS attach)

Question 12

Mechanisms of efferent control of spindle function

Answer 12

1. Control voluntary torments
2. Generate spinal reflex movements
3. Kinaesthesia ( perceive limb and body position and movement in space)

Question 13

Role and mechanism of action of Golgi tendon organ

Answer 13

• Monitor tension on tendons,

Question 14

Mechanisms by which drugs can modulate synaptic transmission in autonomic nervous system

Question 15

Mechanisms by which drugs can modulate synaptic transmission at neuromuscular junction

Answer 15

Inhibit choline transporter (e.g. hemicholinium)
•Block voltage gated Ca2+ channels (e.g. black widow spider venom)
•Block vesicle fusion (e.g. botulinium toxins)
•Use non-depolarising nicotinic receptor blockers (e.g. d-tubocurarine)
•Use depolarising nicotinic receptor blockers (e.g. suxamethoneum = succinylcholine)

Question 16

Consequence of muclulating synaptic transmission in autonomic system at neuromuscular junction