lecture 17 - histamine & anti-histamines

Question 1

What cell is the major source of histamine?

Answer 1

Mast cells

Question 2

What are the progenitor cells of mast cells, which are found in the blood?

Answer 2

Basophils

Question 3

What are the different types of histamine receptors?

Answer 3

H1, H2, H3, H4

Question 4

What are the most clinically relevant histamine receptors?

Answer 4

H1, H2

Question 5

What are the effects of activation of the H1 receptor?

Answer 5

Vasodilation, increased vascular permeability, bronchial smooth muscle constriction, sensory activation (itch/pain)

Question 6

What are the effects of activation of the H2 receptor?

Answer 6

gastric acid secretion stimulation, increased heart rate/CO

Question 7

What is a common example of a 1st generation H1 receptor antagonist?

Answer 7

Promethazine

Question 8

What is the advantage of second generation H1 receptor antagonists over first generation?

Answer 8

They do not cross the blood-brain barrier, so have fewer neurological side effects, such as sedation, dizziness, tinnitus, etc.

Question 9

What is an example of a 2nd generation H1 receptor antagonist?

Answer 9

Loratadine

Question 10

What type of drug is used to treat motion sickness?

Answer 10

H1 receptor antagonists

Question 11

What are the indications for H2 receptor antagonists?

Answer 11

Peptic ulcers, gastroesophageal reflux disorder