General inflammation

Question 1

what are the hallmarks of inflammation?

Answer 1

1. redness – increased blood flow is due to relaxation of vasculature by direct-action of mediators or by the release of vasodilator substances from endothelial cells (e g NO, PGI2).
2. swelling - increased vascular permeability, causing rate of loss of fluid from the vessel to exceed the rate of lymphatic drainage.
3. warm – increased blood flow
4. pain - results from sensitisation of primary afferent neurones (c-fibres) in response to inflammatory mediators
5. loss of function - pain and stiffness that follows swelling.

Question 2

what are the GPCRs for the different types of histamine receptors?

Answer 2

H1 = Gq (more for allergy)
H2= Gs (more for gastric acid secretion)

H3= Gi/o (more for neurotransmitter modulation i.e. autoreceptor)
H4 = unknown (immunomodulation)

Question 3

Main actions of H1

Answer 3

(a) Smooth muscle contraction (*all except arteries)
(b) Increase vascular permeability

(c) Stimulates secretion from all glands
(d) Stimulates sensory fibres (c-fibres and A-delta fibres) in skin

Question 4

Main actions of H2

Answer 4

(a) Stimulates gastric secretion

(b) Inhibit antibody synthesis, T-cell proliferation and cytokine production
(c) Increased chronotropic and inotropic effects (but not enough to compensate for massive vasodilation via H1)

Question 5

Chlorpheniramine

Answer 5

H1 antagonist – 1st gen

sedative

Question 6

Cetrizine, Loratadine

Answer 6

H1 antagonist – 2nd gen

non-sedative

Question 7

Ranitidine, Cimetidine

Answer 7

H2 antagonist

Question 8

uses for H1 antagonists?

Answer 8

allergy, 
hypersensitivities, 
(why you shouldn't drive:)
motion sickness,
mild hypnotic

Question 9

uses of H2 antagonists?

Answer 9

gastric ulcers,

decrease gastric secretion, (especially when NSAID is given)

Question 10

what other moa does OLD H1 antagonists have?

Answer 10

anti-muscarinic activity.

commonly used!

Question 11

moa of bradykinin?

Answer 11

B2 receptors,

inflammatory actions:

1. vasodilator
2. bronchoconstrictor
3. pain sensitivity
4. histamine

Question 12

how are kinnins formed?

Answer 12

breakdown of kininogen

by kallidin