Pharm Test 3 Goz 1

Front 1

Synthesis of Histamine.

Back 1

Histamine is synthesized by the histidine decarboxylase acting on histidine in a single step.

Front 2

Where is Histamine stored (4)?

Back 2

(1) Mast Cells
(2) Basophils
(3) Enterochromaffin-like cells
(4) bran and other organs

Front 3

True/False.
Histamine distribution is related to the distribution of mast cells.

Back 3

TRUE.

Front 4

How is Histamine released?

Back 4

Histamine is released by the binding IgE molecules to a mast cell and being cross-linked by the particular antigen that the IgE recognizes. It requires energy and calcium.

Front 5

What do all Histamine receptors have in common?

Back 5

All are coupled to G-proteins.

Front 6

Name the four receptors for histamine.

Back 6

(1) H1: Gq
(2) H2: Gs
(3) H3: Gi
(4) H4: Gi

Front 7

Describe H1.

Back 7

Gq raises IP3 and raises DAG.
Found on smooth muscle, endothelium, and the brain.

Front 8

Describe H2.

Back 8

Gs raises cAMP.
Found on gastric mucosa, heart, mast cells, brain.

Front 9

Describe H3.

Back 9

Gi lowers cAMP.
Found on brain neuron terminals.

Front 10

Describe H4.

Back 10

Gi lowers cAMP.
Found on eosinophilks, neutrophils, and CD4 T cells.

Front 11

What are H3 receptors similar to?

Back 11

Alpha 2 receptors.

Front 12

Describe the H1 cardiovascular effect.

Back 12

(1) Decrease in Blood pressure and Reflex tachycardia.
(2) Transudation
(3) Pain and Itching via sensory nerve terminals

Front 13

Describe the H3 brain effect.

Back 13

There is decreased release of transmitters such as amines, acetylcholine, and peptides. This is similar to the alpha 2 effect.

Front 14

Describe the interaction between G cels in the stomach and histamine.

Back 14

The G cells produce Gastrin. Gastrin binds to the CCK2 receptor on the enterochromaffin-like cells. It causes the enterochromaffin-like cells to release histamine.

Front 15

Name three receptors present on the parietal cell.

Back 15

(1) H3 (binds to histamine)
(2) CCK2 receptor (gastrin)
(3) M3 Muscarinic Receptor (innervated by Vagus and releases Ache)

Front 16

What happens if gastrin binds to the CCK2 receptors and the Histamine on the H2 receptors and the vagal response on the M3 receptors on the Parietal cells?

Back 16

As a result of these bindings, we get an increase in intracellular Calcium anc cAMP increases.

Front 17

What are the effects of Histamine release from the stomach on G cells?

Back 17

Histamine has an effect on the cytoskeleton. The cytoplasm has pumps and channels. The pumps and channels are inserted into the luminal membrane and in addition to this, there is formation of canaliculi - this increases protons and stomach's acidity

Front 18

What are the effecst of Histamine release from the stomach on parietal cells?

Back 18

Increased intracellular Calcium and cAMP.
Increased ATPase which exchanges the potassium for releaseing a proton - thus, making the stomach more acidic.

Front 19

What do D cells secrete?

Back 19

D cells secrete Somatostatin when the pH is less than 3. The somatostatin binds to the G cells and has a negative inhibitory effect.

Front 20

What is the triple response?

Back 20

(1) Red spot and vasodilation
(2) Raised area or wheel
(3) Reddening or flare (due to axon reflux)

Front 21

What is diphenhydramine?

Back 21

Diphenhydramine (Benedryl) is a H1 blocker. It is a competitve and reversible. All of these are taken orally.

Front 22

What are possible toxicities of diphenhydramine?

Back 22

(1) Drowsiness
(2) Block Muscarinic Receptors - dry mouth, urinary retention, blurred vision

Front 23

Which H1 blockers can be used as Local Anesthetics?

Back 23

(1) Diphenhydramine
(2) Promethazine

Front 24

What is the major difference between first generation and second generation drugs?

Back 24

Second generation drugs are less lipophilic and less willing to cross the BBB. Second generation is further prevented from getting into the BBB from the protein - P-glycoprotein.

Front 25

What are the three 2nd generation H1 Blocker drugs?

Back 25

(1) Fexofenadine
(2) Cetirizine
(3) Loratadine

Front 26

Of the three 2nd generation H1 blockers, which lasts the longest?

Back 26

Loratadine, which is active for 10-20 hours, while fexofenadine and loratadine are active only for 4-6 hours.

Front 27

What is the generic name of Zertec?

Back 27

Zertec = Cetirizine

Front 28

What are the indications of Loratadine?

Back 28

Used for allergic rhinitis.
Also used for urticaria or itching.

Front 29

Name 4 H2 Selective Antagonists.

Back 29

(1) Cimetidine
(2) Ranitidine
(3) Famotidine
(4) Nizatidine

Front 30

What are H2 Selective Antagonists used for?

Back 30

Cimetidine, Ranitidine, Famotidine, and Nizatidine are used in the txt of excessive HCl stomach production.

Front 31

What is the mechanism for H2 Selective Antagonists?

Back 31

They work by blocking the H2 receptor on the parietal cells which secretes HCl.As a result, it will cause a 50-80% reduction in HCl production.

Front 32

What are possible toxicities of Cimetidine, Ranitidine, Famotidine, and Nizatidine?

Back 32

Possible Toxicitis include diarrhea, headache, drowsiness.If you stop administering the drug - you can get something called acid rebound - so you should taper its effects.

Front 33

What are two proton pump inhibtors and what are they given for?

Back 33

(1) Omeprazole
(2) Lansoprazole
(3) Esomeprazole
These are drugs that are actually used in the treatment of extra acid production and acid-reflux disease. They will cause greater than 90% reduction in acid production.

Front 34

Describe how the inactive protein pump drugs become active drugs.

Back 34

§ These drugs are activated when they are converted to a derivative, tetracyclic sulfonamide by a proton-catalyzed reaction that traps the drug in the parietal cell.
§ The active form of the drug binds covalently to cysteine sulfhydryls on the proton pump (the H+, K+, -ATPase).
§ This irreversibly inactivates the proton pump (drug activity continues even after the drug is cleared).

Front 35

In order to prevent digestion in the stomach, how must the proton pump drugs be made?

Back 35

With a coating.

Front 36

Are the proton pump drugs long acting or short acting?

Back 36

Long acting - sense these drugs bind irreversibly - they are no longer active only until a new pump is made.

Front 37

Do tolerancs develop towards the proton pump drugs?

Back 37

No.

Front 38

How should you take the proton pump drugs?

Back 38

30 minutes prior to a meal.

Front 39

What are some toxicities of the proton pump drugs?

Back 39

(1) Diarrhea
(2) Flatulence
(3) 5% of intensive care patients have the probability of developing hospital acquired pneumonia.