boots- Histamine exam 2

Question 1

what tissues can histamine be found in?

Answer 1

GI tract, CNS, dermis, lungs

these are referred to as ‘non-mast cell pool’

Question 2

what is ‘mast cell pool’

Answer 2

histamine is found in mast cells in CT and basophils in circulation

Question 3

T/F

‘**mast cell pool ‘ **consist of rapid turnover- continuous (constitutive) production and release?

Answer 3

FALSE:’

non mast cell pool’ consist of rapid turnover- continuous (constitutive) production and release?

mast cell pool: **stored in secretoy granules, after depletion stores are slowly replenishes

Question 4

what drug can stimulate the release of histamine?

Answer 4

morphine

Question 5

what **drugs ** _inhibit _ histamine release?

Answer 5

cromolyn sodium- ‘mast cell stabilizer;

catecholamines- epi

phosphodiesterase

glucocorticoids

Question 6

what are the other stimulats for release of histamine?

Answer 6

• immune-induced (IgE)
• drug-released
• plant and animal stings
• physical injury or disease that disrupts mast cell

Question 7

H1 receptor activation can lead to what?

Answer 7

• contraction of smooth muscle –> bronchoconstriction
• vasodilation then contraction of vessels –> hypotension, shock and edema
• positive inotropic effect
• CNS stim

Question 8

H2 receptor activation can lead to the following:

Answer 8

• increased gastric secretion
• positive inotropic
• increase heart rate

Question 9

list the 1st generation H1 blockers

Answer 9

• pyrilamine/tripelenamine
• diphenydramine-benedryl
• dimenhydrinate
• chlorpheniramine
• cyproheptadine
• promethazine
• trimeprazine-prednisolone
• meclizine
• cyclizine
• hydroxyzine

Question 10

what 1st generation H1 blocker is used to treat old dog vestibular dz?

Answer 10

meclizine

Question 11

what 1st generation H1 blocker is also used as an appetite stimulant in cats?

Answer 11

cyproheptadine

Question 12

what 1st generation H1 blocker is also used an an anti-emetic, antitussive and sedative?

Answer 12

Diphenydramine (benedryl)

Question 13

what are the 2nd generation H1 blockers?

Answer 13

• astemizole
• terfenadine
• loratadine (claritin)
• fexofenadine (allegra)

Question 14

what generation last longer..

1st or 2nd?

Answer 14

2nd generation

they last 12-24 hours

Question 15

T/F

2nd generation H1 blockers cause sedation

Answer 15

FALSE!!

1st generation H1 blockers cause sedation because cross BBB

Question 16

T/F

1st generation H1 blockers last 12-24 hours

Answer 16

FALSE!!!

1st generation are short. **they last only 3-12 hours, but have a wider distribution and cross BBB

Question 17

what are the H2 blockers?

Answer 17

• cimetidine
• famotidine
• ranitidine and nizatidine

Question 18

which H2 blocker’s immunomodulating effects inhibit T cells and enchance CMI and can treat equine melanoma and reduce gastric acid motility?

Answer 18

Cimetidine

Question 19

what H2 blocker is a _hepatic microsomal enzme inhibito_r?

Answer 19

cimetidine

Question 20

which H2 blocker is used for gastric acid control only?

Answer 20

famotidine

Question 21

which H2 blockers are used for gastric acid and also for their GI Prokinetic activity?

Answer 21

ranitidine and nizatidine