Neurotransmitters Pt. 2

Question 1

What are agonists?

Answer 1

Substances that bind and activate a receptor.

Question 2

What are antagonists?

Answer 2

Substances that bind and block a receptor.

Question 3

What is phenylephrine?

Answer 3

A cold/sinus medication.

Question 4

What receptor does phenylephrine bind to and what is its mode of action?

Answer 4

An adrenergic alpha-1 receptor agonist.

Question 5

What is the function of phenylephrine?

Answer 5

Constricts blood vessels in the nasal mucosa, decreasing mucus production.

Question 6

What is atropine?

Answer 6

A muscarine receptor antagonist.

Question 7

What is the function of atropine?

Answer 7

1. Dilates the pupils.
2. Reduces glandular secretions.
3. Relaxes smooth muscles in the GIT.

Question 8

What is atropine an antidote for?

Answer 8

Chemical warfare agents.

Question 9

What is propranolol?

Answer 9

Nonselective beta blocker.

Question 10

What is the function of propranolol?

Answer 10

1. Decreased HR.
2. Decreased force of contraction
3. Decreased blood pressure.
   *Used to treat hypertension.

Question 11

What are the undesired effects of propranolol?

Answer 11

1. Hypoglycemia.
2. Mild bronchoconstriction.

Question 12

What is autonomic tone?

Answer 12

The balance between the parasympathetic and sympathetic divisions of the ANS, which most organs receive input from.

Question 13

What gland regulates autonomic tone?

Answer 13

The hypothalamus through the upregulation of one ANS division while simultaneously downregulating the other ANS division.

Question 14

What 6 structures are innervated by the sympathetic division only?

Answer 14

1. Adrenal medulla.
2. Erector pili muscle.
3. Kidneys.
4. Most blood vessels.
5. Spleen.
6. Sweat glands.

Question 15

How are tissues only innervated by the sympathetic division only regulated?

Answer 15

By increases and decreases in sympathetic tone.

Question 16

What does the sympathetic division upregulate in response to?

Answer 16

1. Stress, real or perceived.
2. Fear.
3. Rage.

Question 17

What happens when the sympathetic division is activated?

Answer 17

1. ATP synthesis is increased through glycogenolysis and lipolysis.
2. Pupils dilate.
3. Blood pressure increases.
4. Airways dilate.
5. Most visceral blood vessels constrict.
6. Muscular blood vessels dilate.

Question 17

What does the parasympathetic division upregulate in response to?

Answer 17

When the body is at rest and conserving energy.

Question 18

What happens when the parasympathetic division is activated?

Answer 18

1. Salivation.
2. Lacrimation.
3. Urination.
4. Defecation.
5. Digestion.
   *Digestive glands and GIT smooth muscle is active.

Question 19

What is gamma-aminobutyric acid?

Answer 19

An inhibitory CNS neurotransmitter.

Question 20

What 4 portions of the CNS release GABA?

Answer 20

1. Basal ganglia.
2. Cerebellum.
3. Cortex.
4. Spinal cord.

Question 21

What does GABA cause?

Answer 21

1. IPSP through opening Cl- channels.
2. Muscle relaxer.

Question 22

What portion of brain synapses have GABA receptors?

Answer 22

1/3.

Question 23

What 2 drugs utilize the action of GABA?

Answer 23

1. Benzodiazopine (enhances it).
2. Diazepam/valium.

Question 24

Where do the neurons that secrete dopamine originate?

Answer 24

The substantia nigra.

Question 25

Where do the neurons from the substantia nigra terminate?

Answer 25

The basal ganglia.

Question 26

Is dopamine an inhibitory or a stimulatory neurotransmitter?

Answer 26

Inhibitory.

Question 27

What does dopamine cause when it binds to D1 receptors?

Answer 27

Stimulate(stm) adenylate cyclase.

Question 28

What does dopamine cause when it binds to D2 receptors?

Answer 28

Inhibits(inh) adenylate cyclase.

Question 29

What are the functions of dopamine?

Answer 29

1. Addictive behavior. 2. Emotional responses. 3. Pleasurable experiences. 4. Regulate skeletal muscle tone.

Question 30

How does does fescue toxicity occur in mares?

Answer 30

They consume fescue grass that contains the alkaloid ergovaline, which mimics dopamine and binds to D2 receptors.

Question 31

What effect does ergovaline have in the body that is important in pregnant mares?

Answer 31

It suppresses prolactin production, which is essential for milk production and signaling of the final stage of pregnancy.

Question 32

What is the treatment for fescue toxicity?

Answer 32

Domperidone.

Question 33

What is Domperidone?

Answer 33

A paste that acts as a D2 receptor antagonist to relieve the prolactin-depressing effects of alkaloids.

Question 34

What is the cause of Parkinson's Disease?

Answer 34

The destruction of dopamine-secreting nerves causing an imbalance in Ach and DA.

Question 35

What are the signs of Parkinson's Disease?

Answer 35

1. Akinesia. 2. Hypokinesia (Difficulty initiating movement). 3. Involuntary tremors. 4. Muscle rigidity.

Question 36

What age group does Parkinson's Disease normally appear in?

Answer 36

Age 60+.

Question 37

What leads to the destruction of nerve fibers that eventually causes Parkinson's Disease?

Answer 37

Suspected to be environmental chemicals, but genetics may also play a role.

Question 38

How is Parkinson's Disease treated through increasing DA levels?

Answer 38

1. L-Dopa. 2. Deprenyl (MAO inhibitor).

Question 39

How is Parkinson's Disease treated through decreasing ACh levels?

Answer 39

Benzotropine (Blocks ACh effects).

Question 40

How is nitric oxide different than other small molecule neurotransmitters?

Answer 40

It is made as needed, not preformed and stored in vesicles.

Question 41

What does nitric oxide alter when it binds to the post-synaptic neuron/effector tissue?

Answer 41

The intracellular metabolism.

Question 42

Where is nitric oxide released from outside of the nervous system?

Answer 42

Endothelial cells in the blood.

Question 43

What is the function of nitric oxide?

Answer 43

1. Long-term behavior. 2. Long-term memory. 3. Smooth muscle relaxation. 4. Vasodilation.

Question 44

What pharmaceutical makes use of nitric oxide?

Answer 44

Sildenafil/Viagra.

Question 45

What are endorphins and enkephalins classified as?

Answer 45

Neuropeptides, specifically opioid peptides.

Question 46

What are the functions of endorphins and enkephalins?

Answer 46

1. Euphoria. 2. Learning. 3. Memory. 4. Potent analgesic. *Associated with the runner's high.