ANS: Stress Response

Question 1

What are the components of the CNS?

Answer 1

1. Brain

2. Spinal cord

Question 2

What do afferent nerves do?

Answer 2

Sensory neurons, deliver info from external environment to brain

Question 3

What do efferent nerves do?

Answer 3

Motor neurons, deliver info from brain to peripheral structures

Question 4

What does the ANS do?

Answer 4

Part of peripheral nervous system, regulates involuntary functions

Question 5

What comprises the PSNS?

Answer 5

Arises from brain stem via CNS.

CN X Vagus controls 75% of PSNS functions. Also includes spinal and sacral nerves

Question 6

What comprises the SNS?

Answer 6

Arises from the spinal cord via thoracic and lumbar areas.

Includes SNS specific neurotransmitters (catecholamines)

Question 7

What are catecholamines?

Answer 7

Neurotransmitters associated with SNS

1. Norepinephrine
2. Epinephrine
3. Dopamine

Question 8

What are sympathomimetics?

Answer 8

Synthetic drugs that mimic cathecholamines to activate alpha, beta, dopaminergic receptors of SNS

Question 9

How does neurotransmission work?

Answer 9

1. Impulse travels to presynaptic membrane
2. Presynaptic membrane releases NTs into the synapse
3. NTs fit onto specific receptor sites
4. Enough NTs attaching = organ effect

Question 10

What NTs alpha adrenoceptors receptive to?

What types of alpha receptors are there and what do they effect?

Answer 10

Receptive to norepinephrine, epinephrine, dopamine

Alpha 1 receptors effect vascular smooth muscle. Vasoconstriction. Found in systemic vessels, heart, GI tract

Alpha 2 receptors provide negative feedback loop that usually inhibits release of catecholamines

Question 11

What do alpha 2 agonists do?

Answer 11

Targets alpha 2 receptors, activates negative feedback loop, suppresses SNS, calms pt from anxiety, can decrease BP

Question 12

What NTs are beta adrenoceptors receptive to?

What types of beta receptors are there and what do they do?

Answer 12

Receptive to epinephrine (B1), norepinephrine, dopamine

Beta 1 receptors effect the heart

1. Cronotropic (HR)
2. Inotropic (Contractility)
3. Dromotropic (Conduction)

Beta 2 receptors effect the lungs and will cause bronchodilation (smooth muscle relaxation)

Question 13

What NTs are dopaminergic receptors receptive to? What does it do?

Answer 13

Receptive to dopamine. Effects blood vessels to kidney, kidney itself, causes slight diuresis via vasodilation

Question 14

What NTs are present in the PSNS?

Answer 14

Acetylcholine attaches to cholinergic receptors to activate PSNS

Question 15

What would an anti-cholinergic med do?

Answer 15

Suppresses effects of overactive PSNS (Glycopyrralate reduces secretions, drooling)

Question 16

What does epinephrine primarily effect?

Answer 16

Primarily effects Beta 1 receptors and will increase HR, FOC, conduction. Give in cases of bradycardia, not so much with volume issues.

Question 17

What med do you give to vasoconstrict the pt?

Answer 17

Levo, vasopression

Question 18

What med do you give to increase cardiac function or bronchodilate?

Answer 18

Epi

Question 19

How does dopamine dosage effect function?

Answer 19

Low dose –> dopaminergic (renal dose), kidney vasodilation and diuresis
Med dose –> Beta / dopinergic effects. Increase cardiac function
High dose –> Alpha / beta effects. Vasoconstriction